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HELP IT'S HOT!!!!!

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Stephen

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Aug 2, 1999, 3:00:00 AM8/2/99
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It is very hot in my office with no air-conditioning. What is the
maximum temperature that PC's should be running at.

Stephen


Andrew Kressman

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Aug 2, 1999, 3:00:00 AM8/2/99
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Stephen wrote in message <7o4q93$gbg$1...@nclient13-gui.server.virgin.net>...

>It is very hot in my office with no air-conditioning. What is the
>maximum temperature that PC's should be running at.


I think that a lot of components will tolerate up to 70 deg. C, but I'm not
sure. I would be interested to know exactly how much heat things can
tolerate because in this weather my hard disks are getting so hot that I
cannot touch them!! They're right next to each other in the drive bay which
doesn't help....


--
(¯`·.¸¸.·´¯`·-> Andrew Kressman <-·´¯`·.¸¸.·´¯)
and...@kressman.f9.co.uk
http://www.kressman.f9.co.uk
ICQ: 13683199

Jack Peacock

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Aug 2, 1999, 3:00:00 AM8/2/99
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Stephen <sc....@virgin.net> wrote in message
news:7o4q93$gbg$1...@nclient13-gui.server.virgin.net...

> It is very hot in my office with no air-conditioning. What is the
> maximum temperature that PC's should be running at.
>
It's been my experience (I live in the Mojave desert, daily temps in
summer are *normally* 105f/40c) that if you watch your big 17+" monitor,
it will start to fail from too hot ambient temp before the PC does,
assuming normal cooling for the PC. That's usually around 90-95f. In
older PDP-11 days the CPU would start to fail first at around 85f
ambient, but the old VT52s were still running past 90f.
Jack Peacock


Rod Speed

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Aug 3, 1999, 3:00:00 AM8/3/99
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Stephen <sc....@virgin.net> wrote in message
news:7o4q93$gbg$1...@nclient13-gui.server.virgin.net...

> It is very hot in my office with no air-conditioning. What is
> the maximum temperature that PC's should be running at.

There is no nice tidy figure. What matters is how hot the cpu
etc gets and that depends on the room temp, how well the air is
circulated thru the case and how hot the cpu is running anyway.

You'll certainly find that with something that is generating quite a
bit of heat itself, when its not got adequate air circulation over it,
that when a human thinks the room is very hot, it may well be getting
stinking hot, even if it wasnt anything special at normal room temps.

Rod Speed

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Aug 3, 1999, 3:00:00 AM8/3/99
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Andrew Kressman <and...@kressman.f9.co.uk> wrote
in message news:FVnp3.4682$lp.100711@stones...

> I would be interested to know exactly how much heat
> things can tolerate because in this weather my hard
> disks are getting so hot that I cannot touch them!!

The datasheet on the manufacturer's web
site usually says. Which drives specifically ?

> They're right next to each other in the drive bay which doesn't help....

And some sort of fan for cooling them may well help considerably.

Tony Mackin

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Aug 3, 1999, 3:00:00 AM8/3/99
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If its working then it isn't too hot!

Tony

Stephen wrote in message <7o4q93$gbg$1...@nclient13-gui.server.virgin.net>...

>It is very hot in my office with no air-conditioning. What is the
>maximum temperature that PC's should be running at.
>

>Stephen
>
>
>

Darius

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Aug 3, 1999, 3:00:00 AM8/3/99
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<snip>

>
>I think that a lot of components will tolerate up to 70 deg. C, but I'm not
>sure. I would be interested to know exactly how much heat things can

>tolerate because in this weather my hard disks are getting so hot that I
>cannot touch them!! They're right next to each other in the drive bay
which
>doesn't help....
>
My advice is if you can't touch it then it is to hot, yes video cards these
days get hot but but that is why they have a hs/fan to keep it cool.

again if you cannot keep your fingers on it for more than a second then IMHO
it is to hot, I know some IC are designed for operation upto 200°C but they
are the exception and not the norm, most IC's in computers are certainly not
rated to that.

Luc Van der Veken

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Aug 3, 1999, 3:00:00 AM8/3/99
to
Stephen posted:

> It is very hot in my office with no air-conditioning. What is the
> maximum temperature that PC's should be running at.

Pull out the connector of the fan, and show your boss that your
PC crashes because of the heat. If he doesn't give you airco
promptly, you're likely to get at least a new PC ;-)


Ian Stirling

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Aug 3, 1999, 3:00:00 AM8/3/99
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Tony Mackin <tm...@globalnet.co.uk> wrote:
>If its working then it isn't too hot!

Unless there is smoke coming out.
>Tony

>Stephen wrote in message <7o4q93$gbg$1...@nclient13-gui.server.virgin.net>...

>>It is very hot in my office with no air-conditioning. What is the
>>maximum temperature that PC's should be running at.
>>

>>Stephen
>>
>>
>>

Gamma

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Aug 3, 1999, 3:00:00 AM8/3/99
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Jack Peacock <pea...@simconv.com> wrote:
>Stephen <sc....@virgin.net> wrote in message
>news:7o4q93$gbg$1...@nclient13-gui.server.virgin.net...
>> It is very hot in my office with no air-conditioning. What is the
>> maximum temperature that PC's should be running at.
>>
>It's been my experience (I live in the Mojave desert, daily temps in
>summer are *normally* 105f/40c) that if you watch your big 17+" monitor,
>it will start to fail from too hot ambient temp before the PC does,
>assuming normal cooling for the PC. That's usually around 90-95f. In
>older PDP-11 days the CPU would start to fail first at around 85f
>ambient, but the old VT52s were still running past 90f.
> Jack Peacock

Huh. Y'know, that strikes me as such a nice accidental feature
that I think I'd want all monitors to be designed to fail first.
(Well, fail in some non-permanently-damaged way, of course.)

--

Paul Brinkley
ga...@clark.net


barnacle

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Aug 3, 1999, 3:00:00 AM8/3/99
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My Tosh Libretto (yeah I know it's recent but it's already a few generations
out of date so maybe it's not *too* far off thread) shuts down and saves its
internal state and memory to disk on overheating...unfortunately the only time
it overheats is when the ridiculously hot modem card is chuntering away...so
shutdown takes it off line, so it's not quite in the same state as it failed
when it wakes up...damn!

--
barnacle

http://www.nbarnes.easynet.co.uk

Steve Jones

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Aug 3, 1999, 3:00:00 AM8/3/99
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Stephen wrote:
>
> It is very hot in my office with no air-conditioning. What is the
> maximum temperature that PC's should be running at.
>

> Stephen

Your PC's should never be switched on when the temperature exceeds 78F
that's because of course you should all be down the pub having lunch
Stve

Jim Stewart

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Aug 3, 1999, 3:00:00 AM8/3/99
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Stephen wrote:

> It is very hot in my office with no air-conditioning. What is the
> maximum temperature that PC's should be running at.
>

The IBM Technical Reference Manual Personal Computer AT says:

System on 60 to 90 degrees F
System off 50 to 110 degrees F

See, I even kept it on-charter


eup...@cwcom.net

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Aug 4, 1999, 3:00:00 AM8/4/99
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On 1999-08-03 luc...@null.net(LucVanderVeken) said:
:Stephen posted:
:> It is very hot in my office with no air-conditioning. What is the


:> maximum temperature that PC's should be running at.

:Pull out the connector of the fan, and show your boss that your


:PC crashes because of the heat. If he doesn't give you airco
:promptly, you're likely to get at least a new PC ;-)

You may laugh. In the last couple of days we've had a couple of PCs go
down through overheating (33 C - unheard of in Britain) and another guy
was running his PC with the case off, so that the CPU got enough air.

This in a company of less than 10 people.

I think any day where the ambient temperature exceeds 25 C should be
declared a holiday on full pay (or the appropriate recompense for
overtime).
--
the desk lisard communa time's taught the killing game herself

eup...@cwcom.net

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Aug 4, 1999, 3:00:00 AM8/4/99
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On 1999-08-03 Dar...@nospam.nowhere.com said:
:again if you cannot keep your fingers on it for more than a second


:then IMHO it is to hot, I know some IC are designed for operation
:upto 200 C but they are the exception and not the norm, most IC's
:in computers are certainly not rated to that.

Military grade (SN54xx) was always rated between -55 C and 125 C (at
least in the databook I had). SN74xx was rated as (I believe) 0 C to 70
C. Human flesh scalds at 60 C, so the finger test may not be the best
idea around...

Jack Peacock

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Aug 4, 1999, 3:00:00 AM8/4/99
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<eup...@cwcom.net> wrote in message
news:w32q3.1001$Yu4....@news2-hme0.mcmail.com...

> I think any day where the ambient temperature exceeds 25 C should be
> declared a holiday on full pay (or the appropriate recompense for
> overtime).
> --
Hey, I'd go for that! In some parts of the Mojave (like, for instance,
just outside my office window) it stays above 25c for at least 3 months
out of the year, day and night. Some night it doesn't get below 30c.
Those poor guys over in Death Valley (not too far from here) get it even
worse, days pushing 50c out on the salt flats. No idea how they can run
mining machinery on days like that. PCs certainly wouldn't last very
long, embedded controllers really get pushed to the temp limits.

If the A/C fails here the building is uninhabitable within an hour, no
problem in determining when to shut down. The only places that stay
cool without air conditioning are mineshafts and mountain tops above
about 10,000 feet.
Jack Peacock


Tony Turner

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Aug 5, 1999, 3:00:00 AM8/5/99
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Over last summer in I was running our PC in 38 degrees C temps and playing
HL on line at same time. Temp on AOPEN ax6bc board showing 47deg which of
course is only an estimate of chip temp.

Had 1 extra inlet and 1 extra extraction fan in case , both 80mm. Brother in
law under same temp and PC/no extra fans had his temp warning go off at
50deg so extra fans some help. No problem normal applications as Halflife
adds +6deg to case temp due to heat off 3dfx card.

I use a case with dedicated /filtered inlet fan position in front of the
case and another in the rear. This allows easy airflow access to fan.

Probably should on hindsite switched off and went to the beach.
tony

Stephen wrote in message <7o4q93$gbg$1...@nclient13-gui.server.virgin.net>...

>It is very hot in my office with no air-conditioning. What is the
>maximum temperature that PC's should be running at.
>

>Stephen
>
>
>

William Hamblen

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Aug 5, 1999, 3:00:00 AM8/5/99
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On Wed, 04 Aug 1999 21:15:08 GMT, eup...@cwcom.net wrote:

>I think any day where the ambient temperature exceeds 25 C should be
>declared a holiday on full pay (or the appropriate recompense for
>overtime).

My city's average July _minimum_ is 21 C. Average maximum is 32 C.
You would want to close all summer.

Some 35 years ago Hume Fogg High School had an IBM 1620 for the
students. They also ran some administrative jobs on it. The computer
room (really just a class room) was the only air conditioned space in
the building. In the summer the air conditioning couldn't quite keep
up and the machine would have to be turned off on hot days.


Mike Swaim

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Aug 5, 1999, 3:00:00 AM8/5/99
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In alt.folklore.computers eup...@cwcom.net wrote:
: You may laugh. In the last couple of days we've had a couple of PCs go

: down through overheating (33 C - unheard of in Britain) and another guy
: was running his PC with the case off, so that the CPU got enough air.

At my previous job, we had to temporarily replace a server with a
workstation. The only way to keep the drives in the temporary server from
overheating was to run the machine with it's case off, and a fan blowing
on it.

--
Mike Swaim, Avatar of Chaos: Disclaimer:I sometimes lie.
Home: sw...@c-com.net
Alum: sw...@alumni.rice.edu Quote: "Boingie"^4 Y,W&D

Michael Wojcik

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Aug 5, 1999, 3:00:00 AM8/5/99
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In article <w32q3.1001$Yu4....@news2-hme0.mcmail.com>, eup...@cwcom.net writes:
>
> You may laugh. In the last couple of days we've had a couple of PCs go
> down through overheating (33 C - unheard of in Britain) and another guy
> was running his PC with the case off, so that the CPU got enough air.

Last week it hit 40 C (104 F) here in lovely Lincoln, Nebraska,
which is clearly not a place where human beings should live, much
less work. Even with the AC the machines were getting a trifle
warm.

I can't imagine how the pioneers kept their DP infrastructure up
during the summers. (The folks they displaced were smart enough
to relocate when the weather was uncooperative.)


--
Michael Wojcik michael...@merant.com
AAI Development, MERANT (block capitals are a company mandate)
Department of English, Miami University

Ten or ten thousand, does it much signify, Helen, how we
date fantasmal events, London or Troy?
-- Basil Bunting

Philippe Nave

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Aug 5, 1999, 3:00:00 AM8/5/99
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Mike Swaim wrote:
>
> At my previous job, we had to temporarily replace a server with a
> workstation. The only way to keep the drives in the temporary server
> from overheating was to run the machine with it's case off, and a
> fan blowing on it.

I gave an object lesson in refrigeration physics many years ago at a
small software company in Texas; we were renting office space in a
strip-mall type building, and the poor old A/C couldn't keep up with
us. We had ceiling tiles out and box fans put in their place, trying
to cram the hot air up into the attic, and we were still sitting there
in our shorts trying to hammer out code before sweating to death.
The temp in the machine room was about 95 Fahrenheit, and the NCR
minis got flakier and flakier as the day wore on...

Finally, I went out back and got the water hose hooked up. With the
hose spraying a fine mist through the heat exchanger coils on the
A/C compressor, cooling efficiency shot up and we actually started
getting some cold air out the system. Everyone marveled, and within
a couple of minutes the boss came out and asked whether I was willing
to stand there and water the damn compressor so that we could get the
office space cooled down. I handed him the hose.

Philippe

--
=======================================================================
Philippe D. Nave, Jr.| 'Cry havoc, and let slip the dogs of war!'
Denver, Colorado USA | How's my posting? 1-800-DEV-NULL
pn...@lucent.com | Reality 2.0: Score counter, extra men, and hints

Scott Stevens

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Aug 5, 1999, 3:00:00 AM8/5/99
to
Air-condtioning might not help in any case. I remember when a friend gave
me (third-hand) a 'Big Board' system (aka the Xerox 820). It was just the
main board, and not in any kind of enclosure. I was an eager new computer
owner (up til then had had to call computers using a 300 baud acoustic
coupler and one of those monstrous DecWriter printing terminals) and wanted
to do a lot of stuff with it on hot summer days. I didn't have a case for
it yet, so it just lay on the tabletop with all the wires plugged into it
(disk drives, parallel strobed keyboard, video monitor, power supply, etc.).
It would sometimes go unstable, which seemed to be heat related.

I was really getting into computing (this was my first machine with diskette
drives- two 8" 720K ones) and I couldn't do without it. I ended up going
out and buying room air conditioners to cool down the room.

It was a major waste of money. The board still overheated after running
awhile. I discovered that the only way to keep it running stable was to put
little fans that ran the air right across the chips on the board. The room
air conditioners didn't make a bit of difference. Later I mounted the
Bigboard in an old 19" rackmount case, and bolted on the fans to throw air
across the works.

Sometimes it doesn't matter how cool the room is, if there is localized heat
where it will cause trouble. I remember also mounting a strip-type heat
sink on the microprocessor itself (a 40 pin dip, as it was a Z-80), but I
don't recall it helping very much. They always put fans on those new
off-topic (too new) microprocessors these days. Also (off-topic) the people
who run a computer without the cover on it, who think they are doing the
machine a favor often are NOT. A good case is designed so the air flow
passes by the critical components. Running the machine with the cover off
disrupts this air flow, so they'd be better off with the cover in place and
the cooling design of the case intact.

When I was a kid (an IBM brat...) we would go on tours of IBM on family day
once a year. I remember there being a big obvious red switch on the side of
the main computer chassis. I remember asking about it and being told that
it would kill all power to the whole system in an emergency, but that since
it would kill the cooling system as well, the whole system would burn up
quite fast. It was a switch that was never used, needless to say. This
would have been in the mid to late 60's. Does anybody here remember such
switches?


Stephen <sc....@virgin.net> wrote in message
news:7o4q93$gbg$1...@nclient13-gui.server.virgin.net...

Scott Stevens

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Aug 5, 1999, 3:00:00 AM8/5/99
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My boss'es computer had the fan fail once. Nobody noticed it, though, until
one day when I noticed how hot a CD-ROM disk was when extracted from the
drive.

Luc Van der Veken <luc...@null.net> wrote in message
news:37a7145...@news.pandora.be...
> Stephen posted:


>
> > It is very hot in my office with no air-conditioning. What is the
> > maximum temperature that PC's should be running at.
>

Brendan Heading

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Aug 5, 1999, 3:00:00 AM8/5/99
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In article <w32q3.1001$Yu4....@news2-hme0.mcmail.com>,
eup...@cwcom.net writes
>You may laugh. In the last couple of days we've had a couple of PCs go
>down through overheating (33 C - unheard of in Britain) and another guy
>was running his PC with the case off, so that the CPU got enough air.

That's a really, really bad idea. PC cases are designed to allow airflow
with the case on, not off. If the case is off then the fans are less
effective.

--
Brendan Heading, Harold's Cross, Dublin Ireland
"Ohhhhhhh ter beeeeee a jackeeeeeeeeeen laaa.. " ah. Ahem.

William Hamblen

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Aug 6, 1999, 3:00:00 AM8/6/99
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On Thu, 05 Aug 1999 15:30:23 GMT, Mike Swaim <sw...@gemini.c-com.net>
wrote:

> At my previous job, we had to temporarily replace a server with a
>workstation. The only way to keep the drives in the temporary server from
>overheating was to run the machine with it's case off, and a fan blowing
>on it.

The University of Chicago's MANIAC used the oscillating fan approach
to cooling back in the late sixties.


David Given

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Aug 6, 1999, 3:00:00 AM8/6/99
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In article <w32q3.1001$Yu4....@news2-hme0.mcmail.com>,
eup...@cwcom.net writes:
[...]

> You may laugh. In the last couple of days we've had a couple of PCs go
> down through overheating (33 C - unheard of in Britain) and another guy
> was running his PC with the case off, so that the CPU got enough air.

It makes it worse if your office block happens to be a glass box, like
ours, with trendy windows that only open 10cm. It's amazing how much heat
monitors put out.

> I think any day where the ambient temperature exceeds 25 C should be
> declared a holiday on full pay (or the appropriate recompense for
> overtime).

Yeah!

You know, I've often wondered whether it would be possible to remove the
fan from a PSU and replace it with a 30cm carboard chimney attached to the
vents on the back. As the PSU heats up, the chimney should draw enough to
keep air flowing through the PSU (and the computer)...

The PSU fan on my machine once failed; as I was a student at the time, I
didn't replace it, I just removed it completely and ran it with the
computer's lid off. It worked fine, and was astonishingly quiet.

--
+- David Given ---------------McQ-+ "Scuzzy Wuzzy was a bus.
| Work: d...@tao-group.com | Scuzzy Wuzzy caused no fuss.
| Play: dgi...@iname.com | Scuzzy Wuzzy wasn't SCSI, was he?"
+- http://wired.st-and.ac.uk/~dg -+ --- Jordin Kare

gla...@glass2.lexington.ibm.com

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Aug 6, 1999, 3:00:00 AM8/6/99
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In <7odem9$aot$1...@holly.prod.itd.earthlink.net>, "Scott Stevens" <stev...@tcfreenet.org> writes:
>
>When I was a kid (an IBM brat...) we would go on tours of IBM on family day
>once a year. I remember there being a big obvious red switch on the side of
>the main computer chassis. I remember asking about it and being told that
>it would kill all power to the whole system in an emergency, but that since
>it would kill the cooling system as well, the whole system would burn up
>quite fast. It was a switch that was never used, needless to say. This
>would have been in the mid to late 60's. Does anybody here remember such
>switches?
>
>
>Stephen <sc....@virgin.net> wrote in message

Those EPO buttons (Emergency Power Off) exist on quite a few of the
large IBM boxes. They may have an interlock so that, once pushed,
they require a service call to reset. Additionally, I've seen quite
a few computer rooms with EPO buttons by the exit doors.

However, I've never heard about boards overheating as a result of
these being hit. I have heard about disk head crashes on some
ancient equipment though, and I've heard about invalid data being
written as a disk drive gets its power cut halfway through a write
operation (and, on a big system, there are usually quite a few disks
writing something at any particular time).

And, I've heard about the buttons being hit because of smoke pouring
from the back of a system, but, of course, this doesn't count. :*)

Dave

P.S. Standard Disclaimer: I work for them, but I don't speak for
them.


J Church

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Aug 6, 1999, 3:00:00 AM8/6/99
to alt.folklore.computers, aus.computers.ibm-pc, uk.adverts.computer
You could buy chimneys like that to fit on early Apple Macs (the tiny
all-in-one 9" screen ones).

Mike Swaim

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Aug 6, 1999, 3:00:00 AM8/6/99
to
In alt.folklore.computers David Given <d...@tao.co.uk> wrote:
: You know, I've often wondered whether it would be possible to remove the
: fan from a PSU and replace it with a 30cm carboard chimney attached to the
: vents on the back. As the PSU heats up, the chimney should draw enough to
: keep air flowing through the PSU (and the computer)...

Early Macs used convection cooling (as do many monitors). I've seen
several stories about Macs dying from either having stuff put on top of
them (blocking vents), or the Mac being put on its back, so it didn't cool
properly.
A friend killed one of his monitors by blocking the bottom vents with a
towel.

Alan T. Bowler

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Aug 6, 1999, 3:00:00 AM8/6/99
to
Scott Stevens wrote:
>
> When I was a kid (an IBM brat...) we would go on tours of IBM on family day
> once a year. I remember there being a big obvious red switch on the side of
> the main computer chassis. I remember asking about it and being told that
> it would kill all power to the whole system in an emergency, but that since
> it would kill the cooling system as well, the whole system would burn up
> quite fast. It was a switch that was never used, needless to say. This
> would have been in the mid to late 60's. Does anybody here remember such
> switches?

Yes. They were standard equipment in all mainframe shops. Well done
systems also had remotes at the exit doors so the operator could hit
it as he fled a room an already burning room. If you ever had a
situation where use of the emergency power off was appropriate
you had long passed the point where damage from loss of cooling
was a consideration.

Nick Spalding

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Aug 6, 1999, 3:00:00 AM8/6/99
to
gla...@glass2.lexington.ibm.com wrote:

> Those EPO buttons (Emergency Power Off) exist on quite a few of the
> large IBM boxes. They may have an interlock so that, once pushed,
> they require a service call to reset. Additionally, I've seen quite
> a few computer rooms with EPO buttons by the exit doors.

A nice story I was told by the CE concerned. A certain installation
had had a 650 for a while which was replaced by a 1401. After a
parallel run period it was finally decided that the 650 could go. The
CE told the operator of the 650 'OK you can pull that big red button
now', so he did and nothing happened.



> And, I've heard about the buttons being hit because of smoke pouring
> from the back of a system, but, of course, this doesn't count. :*)

I was called out to a 1440 for exactly that reason one Saturday in
1965. The cause was a cooling blower burning itself out while
continuing to blow.
--
Nick Spalding

Nigel J. Carron

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Aug 6, 1999, 3:00:00 AM8/6/99
to
In article <6J$ITyApG...@dnet.co.uk>, Brendan Heading
<b.he...@dnet.co.uk> writes

>That's a really, really bad idea. PC cases are designed to allow airflow
>with the case on, not off. If the case is off then the fans are less
>effective.

Not really the case these days - Some truth for a few Compaq systems
that use passive cooling for their CPU's and other components, but most
systems run cooler sans case.. Mine has 5 different temperature sensors
and ALL run cooler with case off - noisier though..


Nigel J. Carron
Aberdeenshire
Scotland

Luc Van der Veken

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Aug 6, 1999, 3:00:00 AM8/6/99
to
Scott Stevens posted:

>
> I was really getting into computing (this was my first machine with diskette
> drives- two 8" 720K ones) and I couldn't do without it. I ended up going
> out and buying room air conditioners to cool down the room.
>
> It was a major waste of money. The board still overheated after running
> awhile. I discovered that the only way to keep it running stable was to put
> little fans that ran the air right across the chips on the board. The room
> air conditioners didn't make a bit of difference. Later I mounted the
> Bigboard in an old 19" rackmount case, and bolted on the fans to throw air
> across the works.

A couple of years ago, we had a problem with a $400,000 (IIRC)
machine, of which only a moderate number were installed in
Belgium (back then - the number has at least doubled by now).

It would run fine for the first 15 to 20 minutes after powering
it on (cold), and then start to behave erratically.
The company we bought it from sent over a technician - he didn't
find what it was. They sent over a second one to help him: same
story.

I started to search myself while they were out for lunch
(borrowed a can of "cold" from one of them), and managed to
locate the IC on the CPU board that was causing it (it's a big
machine, and they had been searching someplace else because it
looked like a communications problem between the main CPU and
other parts of the machine).

Then it turned out that they (official Sega dealer, BTW) didn't
have a spare mainboard: if we were lucky there would be one in
Scotland, but it might have to come over from Japan... and they
weren't allowed to tamper with the board themselves (the machine
was brand new, and they said they were afraid to void the
warranty if they did anythink else but send the board back).

I took a small heatsink, and glued it onto the IC: the machine
worked fine until a new board arrived, so I guess cyano-acrylic
glue is a good heat conductor ;-)


Rod Speed

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Aug 7, 1999, 3:00:00 AM8/7/99
to

David Given <d...@tao.co.uk> wrote in message news:srmeo7...@pearl.tao.co.uk...

> I've often wondered whether it would be possible to remove the fan
> from a PSU and replace it with a 30cm carboard chimney attached to
> the vents on the back. As the PSU heats up, the chimney should draw
> enough to keep air flowing through the PSU (and the computer)...

Its never going to work as well as a fan.

And you wont get much of a chimney effect with a power supply
anyway because of the way its in a metal box for safety reasons.
The hole for the air only really works properly with a fan over it.

> The PSU fan on my machine once failed; as I was a student at the
> time, I didn't replace it, I just removed it completely and ran it with
> the computer's lid off. It worked fine, and was astonishingly quiet.

Sure, its essentially designed to cover use in the hottest ambient temps.
You can often get away with no fan if you dont experience those and the
power supply isnt delivering anything like its rated output as most dont
anymore with modern spunky little hard drives that dont take much current.

Its not a terrific idea to run modern cpus without
a fan tho, most will die quick smart in hot weather.

Rod Speed

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Aug 7, 1999, 3:00:00 AM8/7/99
to

Brendan Heading <b.he...@dnet.co.uk> wrote
in message news:6J$ITyApG...@dnet.co.uk...
> eup...@cwcom.net writes

>> You may laugh. In the last couple of days we've had a couple of
>> PCs go down through overheating (33 C - unheard of in Britain)

Wota packa wimps, its not unknown to have 10 days over 38C here |-)

>> and another guy was running his PC with
>> the case off, so that the CPU got enough air.

> That's a really, really bad idea.

Nope.

> PC cases are designed to allow airflow with the case on, not off.

Most PC cases arent actually 'designed to allow airflow' at all. They
just have a fan in the power supply and hope for the best. That often
results in quite inadequate performance with the hottest room temps.

> If the case is off then the fans are less effective.

Thats just plain wrong with modern systems with cpu fans.
In that situation you may well get a better result when the
cpu fan can essentially fan ambient temp air thru the cpu
heatsink fins instead of the usually hotter air inside the case.


Mark Forsyth

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Aug 7, 1999, 3:00:00 AM8/7/99
to

gla...@glass2.lexington.ibm.com wrote:

[deletia]

> Those EPO buttons (Emergency Power Off) exist on quite a few of the
> large IBM boxes. They may have an interlock so that, once pushed,
> they require a service call to reset. Additionally, I've seen quite
> a few computer rooms with EPO buttons by the exit doors.

Had one of them lads once. The thing was the usual affair that required
two hands to operate it. It also had the usual warning notice and of
course it was RED. The door button just below it was, in contrast, a
single finger operation the notice very clearly said DOOR and it was
green. I worked at that site, the old Coles Bourke st. head office in
Melbourne, for two and a bit years and in that time the EPO was hit
quite a lot (probably about once a month on average) by people trying to
open the door. The explanations were varied, not valid and enough to
drive you to despair for the human races alleged intelligence...:)

Mark F...

>
> However, I've never heard about boards overheating as a result of
> these being hit. I have heard about disk head crashes on some
> ancient equipment though, and I've heard about invalid data being
> written as a disk drive gets its power cut halfway through a write
> operation (and, on a big system, there are usually quite a few disks
> writing something at any particular time).
>

> And, I've heard about the buttons being hit because of smoke pouring
> from the back of a system, but, of course, this doesn't count. :*)
>

Peter Stephenson

unread,
Aug 7, 1999, 3:00:00 AM8/7/99
to
On Fri, 06 Aug 1999 12:01:31 -0400, in alt.folklore.computers you
wrote:

>Yes. They were standard equipment in all mainframe shops. Well done
>systems also had remotes at the exit doors so the operator could hit
>it as he fled a room an already burning room.

I remember a young secretary leaving the machine room of a big bank in
London and turning round to ask 'is this the button that opens the
door?'. As the entire shift jumped to its feet and shouted 'NO!', she
pressed it. The big red one with EMERGENCY POWEROUT written above it.
It worked just fine.

I'm sure plenty of other people have similar stories, but it was quite
a moment. Afterwards, the ops used to talk about installing an
'emergency phone out' button for times like that. A few seconds of
silence and then ALL the phones start ringing...


Another place I worked had a thing we called 'the flaming printer'.
It's a long story, but there was a chance of data loss in the case of
an emergency (eg a bomb), so we printed the vital details out line by
line. The idea was that one of several designated members of staff
would rip the paper out as they ran for safety in the basement -
presumably trailing flames... A pretty stupid idea, I suspect, but
the thought of it amused us for a long time.

Mike Meredith at home

unread,
Aug 7, 1999, 3:00:00 AM8/7/99
to
Hi

In article <7odem9$aot$1...@holly.prod.itd.earthlink.net>,


"Scott Stevens" <stev...@tcfreenet.org> writes:
> When I was a kid (an IBM brat...) we would go on tours of IBM on family day
> once a year. I remember there being a big obvious red switch on the side of

Once a year ? I don't remember it being that frequent, although
some places could have been different. Definitely rewarding
though --- I saw one of the first ever Winchester drives running
in a Perspex case.

> would have been in the mid to late 60's. Does anybody here remember such
> switches?

Still got one although it's attached to the room rather than a
system.

eup...@cwcom.net

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Aug 7, 1999, 3:00:00 AM8/7/99
to

On 1999-08-05 b.he...@dnet.co.uk said:
:That's a really, really bad idea. PC cases are designed to allow
:airflow with the case on, not off. If the case is off then the fans
:are less effective.

There was a 9" desk fan right next to it. I'm sure that compensated.

Andrew Gabriel

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Aug 7, 1999, 3:00:00 AM8/7/99
to
In article <6J$ITyApG...@dnet.co.uk>,
Brendan Heading <b.he...@dnet.co.uk> writes:
>In article <w32q3.1001$Yu4....@news2-hme0.mcmail.com>,

>eup...@cwcom.net writes
>>You may laugh. In the last couple of days we've had a couple of PCs go
>>down through overheating (33 C - unheard of in Britain) and another guy

>>was running his PC with the case off, so that the CPU got enough air.
>
>That's a really, really bad idea. PC cases are designed to allow airflow
>with the case on, not off. If the case is off then the fans are less
>effective.

If there's any "design" about PC cases today, it's to ensure
the contents get roasted so you have to replace the computer
as soon as possible :-)

I have designed PC cases as you describe, but it's a very long
time since I've seen any commercially available ones which had
been exposed to any real engineering design whatsoever.

--
Andrew Gabriel
Consultant Software Engineer


Kevin Ashley

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Aug 7, 1999, 3:00:00 AM8/7/99
to
Philippe Nave wrote:

>
> Mike Swaim wrote:
> >
> > At my previous job, we had to temporarily replace a server with a
> > workstation. The only way to keep the drives in the temporary server
> > from overheating was to run the machine with it's case off, and a
> > fan blowing on it.
>
> I gave an object lesson in refrigeration physics many years ago at a
> small software company in Texas; we were renting office space in a
> strip-mall type building, and the poor old A/C couldn't keep up with
> us. We had ceiling tiles out and box fans put in their place, trying

[Entertaining story of A/C improvisation snipped]

Many (circa 20) years back we had problems with a DG Nova in a
laboratory during one particularly hot and humid spell in the UK.
There was no air-conditioning in this room, only extractor fans
over the fume cupboards - which had the effect of drawing in more hot
and humid air from outside. We managed to keep the system running
with buckets of dry ice placed on top of the system cabinets. Being
a medical research lab, we had a fair amount of this available.
Nowadays I'd worry about the amount of condensation this might cause
as the air was chilled, but I didn't think about that then and it
didn't seem to be a problem.

We decided against using the liquid nitrogen on the grounds that
its cooling effect might have been a tad too dramatic.

-------------------------------------------------------------------
Kevin Ashley [This is not a signature]

Kevin Ashley

unread,
Aug 7, 1999, 3:00:00 AM8/7/99
to
Scott Stevens wrote:
>
> My boss'es computer had the fan fail once. Nobody noticed it, though, until
> one day when I noticed how hot a CD-ROM disk was when extracted from the
> drive.
>

Then he's luckier than I've been (although you didn't say whether that
was the CPU fan or the PSU fan.) A cheapo Cyrix MII machine I picked
up at auction a few months ago can't manage more than about 5-10
minutes before going very flaky because of CPU fan failure. As far
as I can tell, the _fan_ is overheating. It just slows down as it
gets hot, and seems to start scraping against the heatsink as if the
expansion is making the blades snag. Loosening the attachment screws
helps a bit, but one can't do that too much as the whole thing starts
to rattle unsettlingly if they're too loose.

Kevin Ashley

unread,
Aug 7, 1999, 3:00:00 AM8/7/99
to
Mark Forsyth wrote:
>
> gla...@glass2.lexington.ibm.com wrote:
>
> [deletia]
>
> > Those EPO buttons (Emergency Power Off) exist on quite a few of the
> > large IBM boxes. They may have an interlock so that, once pushed,
> > they require a service call to reset. Additionally, I've seen quite
> > a few computer rooms with EPO buttons by the exit doors.
>
> Had one of them lads once. The thing was the usual affair that required
> two hands to operate it. It also had the usual warning notice and of
> course it was RED. The door button just below it was, in contrast, a
> single finger operation the notice very clearly said DOOR and it was
> green. I worked at that site, the old Coles Bourke st. head office in
> Melbourne, for two and a bit years and in that time the EPO was hit
> quite a lot (probably about once a month on average) by people trying to
> open the door. The explanations were varied, not valid and enough to
> drive you to despair for the human races alleged intelligence...:)

I'm sure the denizens of a.f.u. are replete with experience of
inappropriate use of EPO buttons. One occurred at my current place
of work when the then head of the MVS systems group thought it would
be fun to bring his son (aged about 7 or 8) to see the mighty
electronic brains in our machine room. As any sensible child would,
he pressed the big red button to see what it would do.

The result was two-fold: a management edict banning children from
our place of work and some nifty flip-off plastic covers over
the Big Red Buttons.

Andrew Gabriel

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Aug 7, 1999, 3:00:00 AM8/7/99
to
At my previous workplace, a cleaner, on leaving the computer
room and realising there was no one else in there, reached back
round the door frame to flick off the lights. You guessed it;
off went 55 mini-computers, 4 Sun servers, several racks of
comms equipment and packet switches linking around 20 external
sites, etc. Infact, absolutely everything except the lights...
:-)

The funniest one I heard (probably here a few years back),
was a very senior member of the Pentagon staff, who decided
to take some visitors down to the basement to see the
impressive computer installation. On arriving, he found his
pass wouldn't open the door into the main room, so he pushed
the big bell-push next to it to attract some attention... :-)

Scott Stevens

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Aug 7, 1999, 3:00:00 AM8/7/99
to
Andrew Gabriel <and...@cucumber.demon.co.uk> wrote in message
news:7oh633$1...@cucumber.demon.co.uk...
> --
> Andrew Gabriel
> Consultant Software Engineer

These days there seem to be at least two 'tiers' of PC case designs
available in most 'screwdriver shops'(I speak of the 'clone' market, not the
'compatible' vendors like Compaq.) There are the cheapest-possible cases,
and usually a second set that are priced at about twice as much. Sometimes
there are aesthetic differences between the cases, but there are always
durability and design differences. Cheap cases are made with the thinnest
possible sheet metal, flimsy bezels, and are often difficult to access and
install components into. The more expensive grade cases are usually more
modularized and of a heavier metal. I invariably elect to purchase the
higher grade case, as in my particular circumstances, there will likely be
three or four motherboards in the case during it's lifetime in my posession,
as I tend to upgrade motherboards fairly often. Cooling system design might
not be highly refined in any of these cases, but it's generally better in
the cases that I elect than in the cheapest ones. Also, cable routing is
important to keep in mind. If there's a big ball of ribbon cable blocking
the air it doesn't matter how good the components you choose are.

Scott Stevens
>


Edward Rice

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Aug 7, 1999, 3:00:00 AM8/7/99
to
In article <37AC67CF...@ulcc.ac.uk>,
Kevin Ashley <K.As...@ulcc.ac.uk> wrote:

> The result was two-fold: a management edict banning children from
> our place of work and some nifty flip-off plastic covers over
> the Big Red Buttons.

Anybody wanting to read the alt.folklore.computers earlier discussions on
the "EPO" or "Big Red Button" anecdotes can do a search in Deja.com for
"Big Red Button" and then skim those threads. A lot of good stories were
posted in the threads that Deja turns up with that search string.

ehr

Ian Stirling

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Aug 8, 1999, 3:00:00 AM8/8/99
to
Kevin Ashley <K.As...@ulcc.ac.uk> wrote:
>Scott Stevens wrote:
>>
>> My boss'es computer had the fan fail once. Nobody noticed it, though, until
>> one day when I noticed how hot a CD-ROM disk was when extracted from the
>> drive.
>>

>Then he's luckier than I've been (although you didn't say whether that
>was the CPU fan or the PSU fan.) A cheapo Cyrix MII machine I picked
>up at auction a few months ago can't manage more than about 5-10
>minutes before going very flaky because of CPU fan failure. As far
>as I can tell, the _fan_ is overheating. It just slows down as it

I believe the issue is slack in the bearing, and lack of oil.
Adding a drop of oil, and replacing the label (or putting on another oil
impermeable label, should help.
For a while, of course.


Joe Morris

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Aug 8, 1999, 3:00:00 AM8/8/99
to
Kevin Ashley <K.As...@ulcc.ac.uk> writes:

>I'm sure the denizens of a.f.u. are replete with experience of
>inappropriate use of EPO buttons. One occurred at my current place
>of work when the then head of the MVS systems group thought it would
>be fun to bring his son (aged about 7 or 8) to see the mighty
>electronic brains in our machine room. As any sensible child would,
>he pressed the big red button to see what it would do.

>The result was two-fold: a management edict banning children from


>our place of work and some nifty flip-off plastic covers over
>the Big Red Buttons.

At my PPOE several years ago in a building far far away we didn't
have a scram switch (at that time I hadn't been able to persuade
management that it was needed). It didn't matter: one day our
head operator brought his youngster into the machine room; said
youngster made a beeline for the 360/65 console and pressed the
RESET button.

Thereafter, any accidental operation of a console switch was referred
to as a "child check".

I saw another scram switch near the exit of a computer room (in a
gov'mt agency that would not like to be identified) that had a sign
next to it. In large letters it proclaimed the message:

DO NOT TEST

I always wondered what story might lie behind the need for such a sign,
but I was there for only one day for a special project and never had
an opportunity to ask about it.

Joe Morris

Chris Hedley

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Aug 8, 1999, 3:00:00 AM8/8/99
to
In article <37AC6657...@ulcc.ac.uk>,

Kevin Ashley <K.As...@ulcc.ac.uk> writes:
> Then he's luckier than I've been (although you didn't say whether that
> was the CPU fan or the PSU fan.) A cheapo Cyrix MII machine I picked
> up at auction a few months ago can't manage more than about 5-10
> minutes before going very flaky because of CPU fan failure. As far
> as I can tell, the _fan_ is overheating. It just slows down as it
> gets hot, and seems to start scraping against the heatsink as if the
> expansion is making the blades snag. Loosening the attachment screws
> helps a bit, but one can't do that too much as the whole thing starts
> to rattle unsettlingly if they're too loose.

That sounds all too familiar; I've had nothing but trouble with stock CPU
cooling fans. It seems that in these units either the coils burn out or
the inevitable sleeve bearing wears out in no time (sleeve bearings are
fine in things like car engines where they have a pressurised lubrication
system, but in the dry and often dusty innards of a PC they're a silly
idea) Last time I had a fan failure I was probably lucky to salvage the
CPU, as it was still too hot to touch more than quarter of an hour after
being powered off, and I doubt that the serious vibration from the fan
did any favours either.

I've since replaced the fans with more expensive ones will roller bearings,
and they're much more effective, reliable and quiet. Sigh; it's true that
you get what you pay for; so many PC components are so cheap and crappy
it's a wonder they work at all. The build quality of most PCs I've seen
when compared to workstations such as VAXstations or SGI or Sun things is
absolutely shocking.

Chris.

Chris Hedley

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Aug 8, 1999, 3:00:00 AM8/8/99
to
In article <37AC67CF...@ulcc.ac.uk>,

Kevin Ashley <K.As...@ulcc.ac.uk> writes:
> I'm sure the denizens of a.f.u. are replete with experience of
> inappropriate use of EPO buttons.

My favourite one was a previous manager of mine telling me of his
stint as an operator whilst on his work-experience year at college.
The 14" single-platter disc covers made particularly good frisbees;
you can guess the rest.

There're also several stories involving cleaners doing their stuff
in the computer room, and not finding any free sockets to plug in
their vacuum-cleaner/floor buffer/whatever proceeded either to
unplug one of the minis "just for a few minutes, noone'll notice,"
or use the "clean" power supply, sending lots of lovely spikes to
all the other sensitive equipment using it. Eventually all the
power supplies were hidden under the raised floor, and those that
couldn't be were refitted with nonstandard sockets (I was just waiting
for a cleaner to show up with their odds'n'sods refitted with 30-amp
plugs!)

Chris.

Chris Hedley

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Aug 8, 1999, 3:00:00 AM8/8/99
to
In article <37AB06DB...@thinkage.on.ca>,

"Alan T. Bowler" <atbo...@thinkage.on.ca> writes:
> Yes. They were standard equipment in all mainframe shops. Well done
> systems also had remotes at the exit doors so the operator could hit
> it as he fled a room an already burning room. If you ever had a
> situation where use of the emergency power off was appropriate
> you had long passed the point where damage from loss of cooling
> was a consideration.

That reminds me, random halon dumps were also a good source for much
gnashing of teeth.

Chris.

Peter Wood

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Aug 9, 1999, 3:00:00 AM8/9/99
to
Rod Speed wrote:

> Brendan Heading <b.he...@dnet.co.uk> wrote
> in message news:6J$ITyApG...@dnet.co.uk...

> > eup...@cwcom.net writes
>
> >> You may laugh. In the last couple of days we've had a couple of
> >> PCs go down through overheating (33 C - unheard of in Britain)
>

> Wota packa wimps, its not unknown to have 10 days over 38C here |-)
>

> >> and another guy was running his PC with
> >> the case off, so that the CPU got enough air.
>
> > That's a really, really bad idea.
>

> Nope.


>
> > PC cases are designed to allow airflow with the case on, not off.
>

> Most PC cases arent actually 'designed to allow airflow' at all. They
> just have a fan in the power supply and hope for the best. That often
> results in quite inadequate performance with the hottest room temps.
>

> > If the case is off then the fans are less effective.
>

> Thats just plain wrong with modern systems with cpu fans.
> In that situation you may well get a better result when the
> cpu fan can essentially fan ambient temp air thru the cpu
> heatsink fins instead of the usually hotter air inside the case.

I just put a fan in the case to suck the air out. Can't do any harm.

Pete.

Jordan Bettis

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Aug 9, 1999, 3:00:00 AM8/9/99
to
Peter Wood wrote:
> > Sigh; it's true that
> > you get what you pay for; so many PC components are so cheap and crappy
> > it's a wonder they work at all. The build quality of most PCs I've seen
> > when compared to workstations such as VAXstations or SGI or Sun things is
> > absolutely shocking.
> >
> > Chris.
>
> That's because most people buy the cheapest products, and don't ask questions.
> Be it computers or anything else. You can't blame manufacturers for catering to
> the market. (This is by way of comment, not criticism, of your remarks).

That is also why things like the Celeron Processor are so popular. Intel
realized that their average misinformed consumer looks at two numbers
when buying a PC: the clock speed and the price.

Consequently, they dumped things like cache that, while being
indispensable in today's world of woefully under powered memory (with
relation to processors), is of little consequence to the PC lusers who
can't get past the price tag.

--
Jordan Bettis BTW: ^Omit the OMIT (Jbe...@davesworld.net)
"Suppose I was a congressman, and suppose I was an idiot, but I repeat
myself."
-Twain

Mike Swaim

unread,
Aug 9, 1999, 3:00:00 AM8/9/99
to
Jordan Bettis <Jbett...@davesworld.net> wrote:
: That is also why things like the Celeron Processor are so popular. Intel

: realized that their average misinformed consumer looks at two numbers
: when buying a PC: the clock speed and the price.

Actually, while current Celerons have much smaller caches, the caches
run at the speed of the CPU, so they tend to execute applications at about
the same rate as P2s. They also tend to be fairly overclockable, so a
signifigant majority are running them a lot faster than they're rated.
Over all, they're a pretty good deal.

Peter Wood

unread,
Aug 10, 1999, 3:00:00 AM8/10/99
to
Chris Hedley wrote:

> In article <37AC6657...@ulcc.ac.uk>,


> Kevin Ashley <K.As...@ulcc.ac.uk> writes:
> > Then he's luckier than I've been (although you didn't say whether that
> > was the CPU fan or the PSU fan.) A cheapo Cyrix MII machine I picked
> > up at auction a few months ago can't manage more than about 5-10
> > minutes before going very flaky because of CPU fan failure. As far
> > as I can tell, the _fan_ is overheating. It just slows down as it
> > gets hot, and seems to start scraping against the heatsink as if the
> > expansion is making the blades snag. Loosening the attachment screws
> > helps a bit, but one can't do that too much as the whole thing starts
> > to rattle unsettlingly if they're too loose.
>
> That sounds all too familiar; I've had nothing but trouble with stock CPU
> cooling fans. It seems that in these units either the coils burn out or
> the inevitable sleeve bearing wears out in no time (sleeve bearings are
> fine in things like car engines where they have a pressurised lubrication
> system, but in the dry and often dusty innards of a PC they're a silly
> idea) Last time I had a fan failure I was probably lucky to salvage the
> CPU, as it was still too hot to touch more than quarter of an hour after
> being powered off, and I doubt that the serious vibration from the fan
> did any favours either.
>
> I've since replaced the fans with more expensive ones will roller bearings,
> and they're much more effective, reliable and quiet.

Definitely the way to go.

> Sigh; it's true that
> you get what you pay for; so many PC components are so cheap and crappy
> it's a wonder they work at all. The build quality of most PCs I've seen
> when compared to workstations such as VAXstations or SGI or Sun things is
> absolutely shocking.
>
> Chris.

That's because most people buy the cheapest products, and don't ask questions.
Be it computers or anything else. You can't blame manufacturers for catering to
the market. (This is by way of comment, not criticism, of your remarks).

regards,

Peter.


Alan T. Bowler

unread,
Aug 10, 1999, 3:00:00 AM8/10/99
to
Peter Wood wrote:
>
>
> I just put a fan in the case to suck the air out. Can't do any harm.

Well. The problem is that this pulls air in through openings like
floppy ports and CD drives, and they then act to "protect" the rest
of the box by filtering out the dust hair etc, and deposting it on
read heads. :-(

Cooling should be done by drawing air through a cleanable/changeable
filter and. However, that idea seems to only be known to mainframe
designers these days.

Rod Speed

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Aug 11, 1999, 3:00:00 AM8/11/99
to

Alan T. Bowler <atbo...@thinkage.on.ca> wrote in
message news:37B05D40...@thinkage.on.ca...
> Peter Wood wrote:

The reason for that is that you get a much worse result if the filters
arent regularly cleaned and thats much more likely with PCs.

Its generally recognised that dust isnt really any big deal in
the main body of the case in a non damp environment so its
better to go the non filter route because thats less prone to
major problems seen when filters arent cleaned regularly.

There are a few PC cases that have filters but they are pretty uncommon.

Steve Williams

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Aug 11, 1999, 3:00:00 AM8/11/99
to
It is also extremely difficult to seal a floppy against air ingress, CD's
and other removable drives have similar problems simply because there are
holes in them......

--
Devo

SRV250 & Duke 450 Special

Troy Loveday

unread,
Aug 11, 1999, 3:00:00 AM8/11/99
to
In alt.folklore.computers Steve Williams <st...@bit.net.au> wrote:
>It is also extremely difficult to seal a floppy against air ingress, CD's
>and other removable drives have similar problems simply because there are
>holes in them......

Instead of attempting to seal the front panel of these devices, why not
seal the device body (enclosure)? I'm no expert, but it seems to me
that most of these types of devices generate very little heat anyway.
This would eliminate air flow and dust contamination.

My wife uses a PC for desktop publishing/typesetting in a small quick
printing shop. Her office is next to the press room, which, in spite
of an air filtration system, generates huge amounts of dust consisting
mostly of paper fibers and powder from the presses. Her PC has a QIC
tape drive for backups. Dust will invariably obscure the light pickup
on the BOT/EOT sensor. After a few sessions of disassembling QIC tape
cartridges to re-thread the tape onto the spool, I prepended "clean the
sensor with an alcohol swab" to her backup procedure. No problems
since. I have considered sealing the tape drive body with clear packing
tape, but haven't tried it yet.

--
Troy Loveday e-mail: <tr...@ti.com>
ASIC Product Development / DTM vox: (972) 480-1497
Texas Instruments, Inc. fax: (972) 480-2356
Dallas, Texas "Don't Tread On Me!"

Mike Swaim

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Aug 11, 1999, 3:00:00 AM8/11/99
to
In alt.folklore.computers Troy Loveday <tr...@asic.sc.ti.com> wrote:

: In alt.folklore.computers Steve Williams <st...@bit.net.au> wrote:
:>It is also extremely difficult to seal a floppy against air ingress, CD's
:>and other removable drives have similar problems simply because there are
:>holes in them......

: Instead of attempting to seal the front panel of these devices, why not
: seal the device body (enclosure)? I'm no expert, but it seems to me
: that most of these types of devices generate very little heat anyway.
: This would eliminate air flow and dust contamination.

CD Drives (especially CDR drives) generate a decent amount of heat.
Jaz, Orb and tape drives should also probably be cooled.
There's also the problem of cabling, since a given device might have an
IDE, floppy or SCSI interface.

John Varela

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Aug 11, 1999, 3:00:00 AM8/11/99
to
On Sun, 8 Aug 1999 17:46:54, jcmo...@jmorris-pc.MITRE.ORG (Joe
Morris) wrote:

> I saw another scram switch near the exit of a computer room (in a
> gov'mt agency that would not like to be identified) that had a sign
> next to it. In large letters it proclaimed the message:
>
> DO NOT TEST
>
> I always wondered what story might lie behind the need for such a sign,
> but I was there for only one day for a special project and never had
> an opportunity to ask about it.

The FAA Air Route Traffic Control Centers have long had diesels to
back up the commercial power. When the 9020 computers were installed
in the late 60s, an elaborate UPS was also installed. The story was
told that the FAA headquarters representative at the Denver Center
decided one night during a computer system test to run his own
supplemental test of the UPS/diesel combination. He shut off the
commercial power to the site. The sudden removal of power draw caused
so much back EMF that the entire city of Longmont, Colorado was
blacked out.

I believe this is a true story. I can name the guy who did it.

--
John Varela
to e-mail, remove - between mind and spring

Rod Speed

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Aug 12, 1999, 3:00:00 AM8/12/99
to

Troy Loveday <tr...@asic.sc.ti.com> wrote in
message news:7os7vg$f5v$1...@sarek.dal.asp.ti.com...
> Steve Williams <st...@bit.net.au> wrote

>> It is also extremely difficult to seal a floppy against air
>> ingress, CD's and other removable drives have similar
>> problems simply because there are holes in them......

> Instead of attempting to seal the front panel of these
> devices, why not seal the device body (enclosure)?

In some ways thats even harder, to get the ribbon cable and power
cable to the drives thru that. It could be done with a fancy system where
you have a pair of headers for each cable on the wall of the enclosure but
its likely to be a lot easier to seal the floppy drive and cdrom drive itself.

> I'm no expert, but it seems to me that most of these
> types of devices generate very little heat anyway.

True, the main exception is some cdrom burners which have their own tiny fan.

> This would eliminate air flow and dust contamination.

True, but probably better done by sealing the drive. All you really
need to do that is to seal the back where the connectors plug in from
the rest. Thats quite doable when done when designing the drive.

The other approach that has been used at times is to organise
things so filtered air produces a positive pressure in the case
so the air actually flows out of the floppy and cdrom drives.

Thats got a major risk of the filter not being properly maintained and clogging.

> My wife uses a PC for desktop publishing/typesetting in a small
> quick printing shop. Her office is next to the press room, which,
> in spite of an air filtration system, generates huge amounts of dust
> consisting mostly of paper fibers and powder from the presses.

Hah. One system I had something to do with years ago now, back in
the minicomputer days was part of a monster chicken farming operation,
claimed to be the biggest in the country. It ended up with a fine film of chicken
shit dust all over the boards before they redid the computer building |-)

> Her PC has a QIC tape drive for backups. Dust will
> invariably obscure the light pickup on the BOT/EOT sensor.

The best approach is to air condition the room the computer is in and clean
the room with a vaccum daily. Amazing what a difference that makes.

> After a few sessions of disassembling QIC tape cartridges
> to re-thread the tape onto the spool, I prepended "clean the
> sensor with an alcohol swab" to her backup procedure. No
> problems since. I have considered sealing the tape drive
> body with clear packing tape, but haven't tried it yet.

It probably would work fine depending on how the metal work
is done. You'll find there is a problem where the connectors are
at the back but it may be enough to fix the sensor clogging.

You might find that you have a problem getting the
drives into the bays with the tape on them tho. Might
need to put them in a bay kit and put them in a 5.25" bay.

Troy Loveday

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Aug 12, 1999, 3:00:00 AM8/12/99
to
In alt.folklore.computers Rod Speed <rods...@ozemail.com.au> wrote:

>Troy Loveday <tr...@asic.sc.ti.com> wrote in
>message news:7os7vg$f5v$1...@sarek.dal.asp.ti.com...

>> Instead of attempting to seal the front panel of these


>> devices, why not seal the device body (enclosure)?

>In some ways thats even harder, to get the ribbon cable and power
>cable to the drives thru that. It could be done with a fancy system where
>you have a pair of headers for each cable on the wall of the enclosure but
>its likely to be a lot easier to seal the floppy drive and cdrom drive itself.

Sorry, I wasn't clear. That's what I was suggesting: sealing the
device body, not the device mounting enclosure.

[snip]

>> My wife uses a PC for desktop publishing/typesetting in a small
>> quick printing shop. Her office is next to the press room, which,
>> in spite of an air filtration system, generates huge amounts of dust
>> consisting mostly of paper fibers and powder from the presses.

>Hah. One system I had something to do with years ago now, back in
>the minicomputer days was part of a monster chicken farming operation,
>claimed to be the biggest in the country. It ended up with a fine film of chicken
>shit dust all over the boards before they redid the computer building |-)

Dang! I thought paper dust was bad. Probably some feather particles
in there too. Allergen City.

[snip]

>> ... I have considered sealing the tape drive


>> body with clear packing tape, but haven't tried it yet.

>It probably would work fine depending on how the metal work
>is done. You'll find there is a problem where the connectors are
>at the back but it may be enough to fix the sensor clogging.

>You might find that you have a problem getting the
>drives into the bays with the tape on them tho. Might
>need to put them in a bay kit and put them in a 5.25" bay.

Yes, unless I could avoid the side rail mount area. Besides, the
QIC drive is already in a 5.25" bay using extended mounting rails.
Perhaps I'll try this sometime...

Martin Ibert

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Aug 12, 1999, 3:00:00 AM8/12/99
to
On 11 Aug 1999 16:22:08 GMT, Troy Loveday <tr...@asic.sc.ti.com>
wrote:

>Instead of attempting to seal the front panel of these devices, why not

>seal the device body (enclosure)? I'm no expert, but it seems to me


>that most of these types of devices generate very little heat anyway.

CD-ROM drives, especially un-folklore-worthy high-speed ones, generate
a lot of heat. I've had CD's come out of drives so hot they were
uncomfortable to touch.
--
>> Please visit http://www.ibert.com/ for further information. <<
-----------------------------------------------------------------
Blind faith in your leaders, or in anything, will get you killed!
-----------------------------------------------------------------
Remember the heroes of Tiananmen Square, Beijing, P. R. of China!

Julian Thomas

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Aug 13, 1999, 3:00:00 AM8/13/99
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In <PXSs7Qc20D1F-p...@user-2ivei3m.dialup.mindspring.com>, on
08/11/99
at 06:43 PM, jva...@mind-spring.com (John Varela) said:

>The FAA Air Route Traffic Control Centers have long had diesels to back
>up the commercial power. When the 9020 computers were installed in the

>late 60s, an elaborate UPS was also installed. The story was told....

On a related note, the machines were built and tested at IBM Poughkeepsie
(based on the 360 mod 50 for the first version of the 9020). So one day
they enabled the UPS, tested the switchover, and then disconnected it
again - a few hours before the great blackout of 1965<?> hit the
Northeast.


--
Julian Thomas: jt 5555 at epix dot net http://home.epix.net/~jt
remove numerics for email
Boardmember of POSSI.org - Phoenix OS/2 Society, Inc http://www.possi.org
In the beautiful Finger Lakes Wine Country of New York State!
-- --
Air conditioned environment - Do not open Windows.


Eric Smith

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Aug 13, 1999, 3:00:00 AM8/13/99
to
jt5...@epix.net (Julian Thomas) writes about the IBM 9020 computers used
by the FAA:

> On a related note, the machines were built and tested at IBM Poughkeepsie
> (based on the 360 mod 50 for the first version of the 9020). So one day

From the perspective of a programmer, did the 9020 exhibit any architectural
differences from the 360?

Kevin Michael Vail

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Aug 13, 1999, 3:00:00 AM8/13/99
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J Church <j...@ljchurch.co.uk> wrote:

> You could buy chimneys like that to fit on early Apple Macs (the tiny
> all-in-one 9" screen ones).

I had one of those--it looked kind of odd, but it was certainly quiet.
I wonder why they can't^H^H^H^H^Hdon't make a computer that doesn't need
a fan...they make audio amplifiers without fans and some of those push
more power through than my lowly iMac does.

> David Given wrote:
>
> > You know, I've often wondered whether it would be possible to remove the
> > fan from a PSU and replace it with a 30cm carboard chimney attached to the
> > vents on the back. As the PSU heats up, the chimney should draw enough to
> > keep air flowing through the PSU (and the computer)...
--
Kevin Michael Vail | I would rather have a mind opened by wonder
ke...@vailstar.com | than one closed by belief. -- Gerry Spence

John Varela

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Aug 14, 1999, 3:00:00 AM8/14/99
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On Fri, 13 Aug 1999 23:28:18, Eric Smith
<eric-no-s...@brouhaha.com> wrote:

> From the perspective of a programmer, did the 9020 exhibit any architectural
> differences from the 360?

The 9020A was all 360/50 parts assembled into a multiprocessor
architecture. Three or four CPUs were "Compute Elements", another 3
CPUs, with access only to MACH memory (later modified to access main
memory), served as "I/O Control Elements", and then there were (up to
12?) "Storage Elements". The instruction set was standard 360 except
for the addition of instructions having to do with configuring the
multiprocessor system. An online system consisted of 3 of the 4
Compute Elements, 2 of the 3 I/O Control Elements, and n-1 Storage
Elements. The idea was instead of duplexing the very expensive
hardware, you could run with one each Compute, I/O Control, and
Storage Elements in an offline system and if an online element failed
pre-empt the needed unit from the offline system. The offline system
was a computer capable of running hardware diagnostics, processing
recorded data from the online system, and so forth.

Neither system ran OS/360. The online system ran a real-time OS
called the NAS Monitor (NAS = National Airspace System), which could
be executed from any of the Compute Elements at any time, and any
Computer Element could execute a program anywhere in the memory
configured in the online syustem. That is, if a Compute Element
needed something to do, it would execute the Dispatcher and perhaps
start executing a program that had started in another Compute Element
and been interrupted. The offline system ran under NOSS, the NAS
Operational Support System.

We (MITRE) opposed the multiprocessor concept, favoring a fully
duplexed system, on the grounds that the field would need a spare
system in order to test out new software deliveries and ATC data
updates before taking them operational. We were right. The 9020As
and Ds were replaced by duplex 3083s about 15 years ago, and until
then the automated systems were taken down regularly for software
testing.[1] The online 3083 runs the old NAS Monitor, suitably
modified to reconfigure a duplex instead of a multiprocessor system.
The offline system runs VM, with a copy of the entire online software
ready in the V=R portion of memory. I believe the FAA is now
replacing (or has replaced) the 3083s.

IBM proposed models B and C but none were ever built and I don't
recall what they were. The 9020D used 360/65 CPUs and Storage but
retained the 360/50 I/O Control Elements. The 9020E was similar to
the 9020D, was used in the display system, and had special
instructions for processing display data and also special display
refresh memory units.

[1] Actually, the field kept taking the online system down even after
they had a duplex system and no one in headquarters could figure out
why they did that. Eventually someone figured out that if they took
the offline system for testing they would have to run the online
system without a backup[2], and if the online system failed the
facility would be charged with a system failure. But if they
SCHEDULED taking the whole system down, then they weren't charged with
a failure. I don't know how that was ever resolved and for all I know
they're still taking the systems down every night.

[2] Well, actually, there is a backup that is both hardware and
software diverse from the main system, but it's less capable, as it
processes only radar, not flight plans. It's what they used when they
unnecessarily took the main system down for maintenance, and IT does
NOT have a backup. Ah! The ways of bureaucracy!

Rod Speed

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Aug 14, 1999, 3:00:00 AM8/14/99
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Kevin Michael Vail <ke...@vailstar.com> wrote in
message news:1dwhr3f.1yketawp67lsN@[192.168.0.4]...
> J Church <j...@ljchurch.co.uk> wrote

> I wonder why they can't^H^H^H^H^Hdon't make
> a computer that doesn't need a fan...

They can and do, plenty of laptops and notebooks dont have fans.

> they make audio amplifiers without fans and some of those
> push more power through than my lowly iMac does.

Audio amps are quite different. They pump the bulk of the
power out thru the speakers. Computers dont pump power
out like that. The heat that the fan fans away is the result
of the internal power dissipation in stuff like the cpu etc.
All those transistors, which audio amps dont have either.


Eric Smith

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Aug 14, 1999, 3:00:00 AM8/14/99
to
jva...@mind-spring.com (John Varela) writes:
> I believe the FAA is now
> replacing (or has replaced) the 3083s.

I read in some trade rag (possibly TechWeek, but I'm not certain) an
article claiming that the FAA was being forced to replace the 3083s because
IBM could not guarantee them to be Y2K compliant. This seems dubious to
me.

Why would replacing the hardware make the system any more Y2K compliant?
Almost all Y2K problems are software problems.

What hardware in a 3083 would be non-Y2K-compliant? Does it have a TOY
clock?

If the 3083 does have an non-Y2K-compliant TOY clock, wouldn't it be simple
enough to hack NAS to ignore it, and either get the system time from manual
input when the system is booted, or from some other external source, such as
a GPS receiver?

And does NAS really need to know the current correct date?

On the other hand, I can easily believe that IBM would not guarantee that
3083s are Y2K compliant. Most companies won't guarantee that their
*current* products are Y2K compliant, let alone stuff that's over fifteen
years old.

John Varela

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Aug 14, 1999, 3:00:00 AM8/14/99
to
On Sat, 14 Aug 1999 08:37:11, Eric Smith
<eric-no-s...@brouhaha.com> wrote:

> jva...@mind-spring.com (John Varela) writes:
> > I believe the FAA is now
> > replacing (or has replaced) the 3083s.
>
> I read in some trade rag (possibly TechWeek, but I'm not certain) an
> article claiming that the FAA was being forced to replace the 3083s because
> IBM could not guarantee them to be Y2K compliant. This seems dubious to
> me.
>
> Why would replacing the hardware make the system any more Y2K compliant?
> Almost all Y2K problems are software problems.

This came up here (afc) several years ago, and I too was skeptical. I
checked with a knowlegdeable person still working with FAA and he said
the problem was IBM wouldn't guarantee the maintenance firmware: the
systems might think they hadn't been serviced for a century and shut
themselves down. There was, supposedly, no one still employed at IBM
who knew the 3083 firmware. Later I was told that FAA had hired some
IBM retirees who checked the firmware and found no problem. Still
later, I saw reference in an FAA e-newsletter to a program that sounds
like a replacement of the 3083s. Given their age, that's probably not
a bad idea regardless of Y2K.



> What hardware in a 3083 would be non-Y2K-compliant? Does it have a TOY
> clock?
>
> If the 3083 does have an non-Y2K-compliant TOY clock, wouldn't it be simple
> enough to hack NAS to ignore it, and either get the system time from manual
> input when the system is booted, or from some other external source, such as
> a GPS receiver?
>
> And does NAS really need to know the current correct date?

The original cause of my skepticism (as above) is that the air traffic
control system works in real time. It knows about seconds, minutes,
and hours, and because of pre-filed air carrier flight plans it knows
about days of the week, but it knows nothing about any longer time
period. The worst problem that could occur in the operational
software would be that it would think 1/1/2000 was 1/1/1900, get the
day of the week wrong, and pre-load the wrong air carrier flight
plans. This would cause confusion and delay, but no aluminum would
fall out of the sky.



> On the other hand, I can easily believe that IBM would not guarantee that
> 3083s are Y2K compliant. Most companies won't guarantee that their
> *current* products are Y2K compliant, let alone stuff that's over fifteen
> years old.

Exactly.

Anne & Lynn Wheeler

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Aug 14, 1999, 3:00:00 AM8/14/99
to

the 3081/3/4 (370s & beyond) has 64bit tod clock with bit 12 being a
microsecond (although architecture didn't require that all/any machine
actually provide microsecond resolution). that made bit 32 slightly
more than a second. its epoch was first day of this century (i
actually got to spend 3 months with some other people resolving what
that was).

most groups initially set zero to 1970 ... rather than the start of
the century (and the rest set it to a year earlier than the start of
the century). with bit 32 slightly larger than a second (1024/1000),
2**32+ seconds (clock period) is almost 140 years ... with epoch at
start of this century it carries well past year 2000.

for more detailed description of current 390 architecture (effectively
a superset) see:

http://ppdbooks.pok.ibm.com:80/cgi-in/bookmgr/bookmgr.cmd/BOOKS/DZ9AR004/CCONTENTS

(although most of the time I find that this url is not operational on
the weekend)

the guy that ran the FAA project went on to be president of IBM's FSD
(now owned by loral) & then left and formed his own company. I believe
he retired last summer.

--
--
Anne & Lynn Wheeler | ly...@adcomsys.net, ly...@garlic.com
http://www.garlic.com/~lynn/ http://www.adcomsys.net/lynn

Anne & Lynn Wheeler

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Aug 14, 1999, 3:00:00 AM8/14/99
to

total aside ... 3083s were never intended to be built just 3081 and
3084. IBMs SMPs prior to the 3081 were two totally independent
machines cobbled together ... so that the components could actually be
unhooked and run as two independent processors. running as
multiprocessor the machines were typically slowed down 15% of so to
allow for memory contention resolution (and in cache machines to
handle cache invalidation signals). when run as two independent
processors the machines would run at full speed.

the 3081 was two processors in a single box ... it was not possible to
partition it and run it as two independent machines. the 3084 was two
3081 tied together to make a 4-way SMP.

The initial 3081 ... 3081D was also only about 5mips per processor
... hardly showing any performance improvement over the 3033. It
wasn't until the 3081K machines that it started to show over 7mips per
processor.

ACP/TPF (airline res system) didn't have any SMP support (although
they would take VM and could run two copies of ACP/TPF on 2-way
system) ... the ACP/TPF market was looking for flat-out fast
performance uniprocessor thruput ... which wasn't available on the
308x line. To satisfy the ACP/TPF market, a 3083 uniprocessor was
built ... which immediately picked up a 15% processor hardware thruput
(and somewhat reduced the cost of the 2nd processor which they
couldn't effectively use ... but there was a lot of stuff done in the
3081 adding the 2nd processor w/o doubling the cost).

Anne & Lynn Wheeler

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Aug 14, 1999, 3:00:00 AM8/14/99
to

i somewhat misspoke ... we didn't spend 3 months just on how to set
the clock ... i.e. operator specifies the current time (yymmdd,
hhmmss, etc) and have to calculate the binary value since the epoch to
load into the clock ... we also tried to figure out how to deal with
things like leap seconds (by comparison leap years are easy ... leap
seconds are unpredictable my be one, more than one, or none ... and
can also be positive or negative ... and are effectively decided at
the last moment).

Julian Thomas

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Aug 14, 1999, 3:00:00 AM8/14/99
to
In <qhlnbf6z...@ruckus.brouhaha.com>, on 08/13/99
at 04:28 PM, Eric Smith <eric-no-s...@brouhaha.com> said:

>From the perspective of a programmer, did the 9020 exhibit any
>architectural differences from the 360?

I'm sure that there were some extensions to the instruction set, but
wasn't close enough to either the programming or the design to know what
they were.



--
Julian Thomas: jt 5555 at epix dot net http://home.epix.net/~jt
remove numerics for email
Boardmember of POSSI.org - Phoenix OS/2 Society, Inc http://www.possi.org
In the beautiful Finger Lakes Wine Country of New York State!
-- --

It is interesting to note that before the advent of Microsoft
Windows, `GPF' was better known for its usage in plumbing:
Gallons Per Flush


Gilbert Saint-flour

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Aug 14, 1999, 3:00:00 AM8/14/99
to
In <uyafec...@adcomsys.net>, on 14 Aug 1999 at 15:57, Anne & Lynn
Wheeler <ly...@adcomsys.net> said:

>http://ppdbooks.pok.ibm.com:80/cgi-in/bookmgr/bookmgr.cmd/BOOKS/DZ9AR004/CCONTENTS

>(although most of the time I find that this url is not operational on
>the weekend)

The URL has changed some months ago, try the new one:

http://www.s390.ibm.com/bookmgr-cgi/bookmgr.cmd/BOOKS/DZ9AR004/

Gilbert Saint-flour

donald tees

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Aug 14, 1999, 3:00:00 AM8/14/99
to
Kevin Michael Vail wrote in message <1dwhr3f.1yketawp67lsN@

>I had one of those--it looked kind of odd, but it was certainly quiet.

>I wonder why they can't^H^H^H^H^Hdon't make a computer that doesn't need

>a fan...they make audio amplifiers without fans and some of those push


>more power through than my lowly iMac does.


Run it at 1/10 clock speed, and I'll bet you could do without the fan.

;<)

David Horvath, CCP

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Aug 14, 1999, 3:00:00 AM8/14/99
to
In article <qh672ip...@ruckus.brouhaha.com>,
eric-no-s...@brouhaha.com says...

>
>jva...@mind-spring.com (John Varela) writes:
>> I believe the FAA is now
>> replacing (or has replaced) the 3083s.
>
>I read in some trade rag (possibly TechWeek, but I'm not certain) an
>article claiming that the FAA was being forced to replace the 3083s because
>IBM could not guarantee them to be Y2K compliant. This seems dubious to
>me.
>
>Why would replacing the hardware make the system any more Y2K compliant?
>Almost all Y2K problems are software problems.
>
>What hardware in a 3083 would be non-Y2K-compliant? Does it have a TOY
>clock?

I remember reading somewhere that the issue was not the hardware so much as the
operating system. The 3083 can't run ESA versions of IBM's operating systems
(VM or MVS) because it is missing hardware assists.

I think the 3083's (3083J) ran VM/XA and MVS/XA (a version prior to ESA). IBM
dropped official support for 'XA years ago and had no financial incentive
(i.e., the ability to sell many copies) to make 'XA Y2K-ready.

I doubt the FAA was willing to pay IBM time and materials for rooms full of
consultants (programmers *and* testers) to perform the upgrade. And that's
assuming that IBM still has the source code with the proper versioning. And
I'm sure that IBM does not have rooms full of 3083's sitting around for them to
test on.

It also means that the FAA has to buy new equipment (revenue for IBM) and IBM
gets to drop service on old machines.

--
David B. Horvath, CCP dhor...@nosuch.cobs.com
Consultant, International Lecturer, Adjunct Professor
Author of "UNIX for the Mainframer" and other books.
*** remove "nosuch." when replying ***


Rod Speed

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Aug 15, 1999, 3:00:00 AM8/15/99
to

Huge <hu...@nospam.demon.co.uk> wrote in
message news:7p3868$f...@axalotl.demon.co.uk...
> Rod Speed <rods...@ozemail.com.au> writes

>> The heat that the fan fans away is the result of the
>> internal power dissipation in stuff like the cpu etc. All
>> those transistors, which audio amps dont have either.

> Audio amps don't have transistors?

Never said that. They clearly have far fewer than
the average PC. Than even just the average PC cpu.


barnacle

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Aug 15, 1999, 3:00:00 AM8/15/99
to
The difference being that (most) amps have transistors which spend their life
with a potential diffenece across 'em and current flowing through 'em...hence
heat is generated as a function of the output volume (I'm only looking at the
output stage here); whereas cpu transistors (in this glorious cmos age)
effectively only use current when they're switching...and not very much of
that - it's just that there are *so* many of them and they switch so fast...


--
barnacle

http://www.nbarnes.easynet.co.uk

Eric Smith

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Aug 15, 1999, 3:00:00 AM8/15/99
to
I asked:

> I read in some trade rag (possibly TechWeek, but I'm not certain) an
> article claiming that the FAA was being forced to replace the 3083s because
> IBM could not guarantee them to be Y2K compliant. This seems dubious to
> me.

dhor...@nosuch.cobs.com (David Horvath, CCP) replied:


> I remember reading somewhere that the issue was not the hardware so much as
> the operating system. The 3083 can't run ESA versions of IBM's operating
> systems (VM or MVS) because it is missing hardware assists.

Which is surely a complete non-issue, since the FAA systems in question
don't run ANY version of VM or MVS, much less a current version? My
understanding based on John Varela's post is that they run a completely
custom OS called "NAS Monitor".

So moving to a new hardware platform can hardly be expected to magically
render NAS Monitor Y2K-compliant.


Jim Saum

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Aug 15, 1999, 3:00:00 AM8/15/99
to
In article <qh672ip...@ruckus.brouhaha.com>, Eric Smith
<eric-no-s...@brouhaha.com> wrote:

>jva...@mind-spring.com (John Varela) writes:
>> I believe the FAA is now
>> replacing (or has replaced) the 3083s.
>

>I read in some trade rag (possibly TechWeek, but I'm not certain) an
>article claiming that the FAA was being forced to replace the 3083s because
>IBM could not guarantee them to be Y2K compliant. This seems dubious to
>me.

Another reason was a serious shortage of spares for the TCM's (Thermal
Conduction Modules) for the 3083's. (The TCM's are circuit packages
that couple to the machine's cooling system.)

- Jim Saum

Ariel Scolnicov

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Aug 15, 1999, 3:00:00 AM8/15/99
to
"donald tees" <don...@willmack.com> writes:

Yeah, but try running your audio amp at 1/10 "clock speed", and see
what it sounds like...

--
Ariel Scolnicov

K. C. Lee

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Aug 15, 1999, 3:00:00 AM8/15/99
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John Varela

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Aug 15, 1999, 3:00:00 AM8/15/99
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On Sun, 15 Aug 1999 07:56:13, Eric Smith
<eric-no-s...@brouhaha.com> wrote:

> Which is surely a complete non-issue, since the FAA systems in question
> don't run ANY version of VM or MVS, much less a current version? My
> understanding based on John Varela's post is that they run a completely
> custom OS called "NAS Monitor".

Correction: the offline/standby system does run VM. Under VM are the
NAS Monitor and a complete NAS operational system (standing by to take
over the operational job), MVS, potentially another copy of NAS in a
virtual machine for testing, and there may still be some NOSS
applications in use. VM was modified so that when failure of the
online computer is detected VM commits suicide and turns the machine
over to the NAS Monitor. If I recall correctly, the switchover takes
about 10 seconds. Obviously anything going on in any MVS jobs is
lost.

chris ulrich

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Aug 16, 1999, 3:00:00 AM8/16/99
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In article <yzq3dxl...@compugen.co.il>,
Ariel Scolnicov <ari...@compugen.co.il> wrote:
%%"donald tees" <don...@willmack.com> writes:
%%
%%> Kevin Michael Vail wrote in message <1dwhr3f.1yketawp67lsN@
%%>
%%> >I had one of those--it looked kind of odd, but it was certainly quiet.
%%> >I wonder why they can't^H^H^H^H^Hdon't make a computer that doesn't need
%%> >a fan...they make audio amplifiers without fans and some of those push
%%> >more power through than my lowly iMac does.
%%>
%%>
%%> Run it at 1/10 clock speed, and I'll bet you could do without the fan.
%%>
%%> ;<)
%%
%%Yeah, but try running your audio amp at 1/10 "clock speed", and see
%%what it sounds like...

I run my computer with only one fan -- the CPU fan on a celeron 300a
(running at 300mhz). I took the rest of the fans out of the computer
and I run the CPU fan at 5v instead of 12v. When the hard disk is not
spinning, the computer is totally silent. When the hard disk is spinning,
it makes about as much noise as a VCR playing a tape. When I ran the
celeron without a fan, it got *very* hot but still worked; now it just
gets hot. The inside of the computer also gets pretty hot, but the worst
that can happen is that I'll eventually burn up the hard disk. I live in
a 3rd floor apartment in the middle of the desert, so it sometimes gets
very hot in the apartment, but the computer has yet to crash for any
reason (I run linux on it).
There is no reason for smaller, slow consumer grade computers to be
as noisy as they are.
chris

Julian Thomas

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Aug 17, 1999, 3:00:00 AM8/17/99
to
In <37b60...@news.dca.net>, on 08/14/99
at 08:50 PM, dhor...@nosuch.cobs.com (David Horvath, CCP) said:

>>What hardware in a 3083 would be non-Y2K-compliant? Does it have a TOY
>>clock?

I think that whoever said it was most likely the service processor code
had this one right.



--
Julian Thomas: jt 5555 at epix dot net http://home.epix.net/~jt
remove numerics for email
Boardmember of POSSI.org - Phoenix OS/2 Society, Inc http://www.possi.org
In the beautiful Finger Lakes Wine Country of New York State!
-- --

Why does the hardware keep getting faster, and the software slower?


fungus

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Aug 19, 1999, 3:00:00 AM8/19/99
to

Rod Speed wrote:
>
> There are a few PC cases that have filters but they are pretty uncommon.
>

My cheap clone does!!!!

I found it the other day, after owning the machine for two years...the
front part of the case slides off to the left to reveal a hidden filter.


--
<\___/>
/ O O \
\_____/ FTB.

Rod Speed

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Aug 20, 1999, 3:00:00 AM8/20/99
to

fungus <fun...@egg.chips.and.spam.com> wrote in message news:37BC0051...@egg.chips.and.spam.com...
> Rod Speed wrote:

>> There are a few PC cases that have filters but they are pretty uncommon.

> My cheap clone does!!!!

> I found it the other day, after owning the machine for two years...

> the front part of the case slides off to the left to reveal a hidden filter.

Pretty smart move given that the biggest problem with the use
of filters is that they clog up if you dont keep cleaning them.

brainless

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Aug 20, 1999, 3:00:00 AM8/20/99
to

Rod Speed wrote in message ...

>
>> I found it the other day, after owning the machine for two years...
>> the front part of the case slides off to the left to reveal a hidden
filter.
>
>Pretty smart move given that the biggest problem with the use
>of filters is that they clog up if you dont keep cleaning them.
>
Thus reducing air flow, with consequent heat increase

Eric Smith

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Aug 20, 1999, 3:00:00 AM8/20/99
to
I asked:

> What hardware in a 3083 would be non-Y2K-compliant? Does it have a TOY
> clock?

jt5...@epix.net (Julian Thomas) writes:
> I think that whoever said it was most likely the service processor code
> had this one right.

And what horrible calamity would happen if the service processor thought
it was the wrong date (such a 1-JAN-1900)?

In all the Y2K mayhem, a lot of people seem to have forgotten that some
systems that aren't Y2K compliant don't actually need to be.

Note that I'm not suggesting that the FAA shouldn't replace the old 3083
systems. I'm just dubious of the claim that it is necessitated by the
Y2K problem.

Rod Speed

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Aug 21, 1999, 3:00:00 AM8/21/99
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brainless <yi...@dial.pipex.com> wrote in
message news:7pjca6$r9e$1...@lure.pipex.net...

Yeah, and ultimately something dying from overheating if you're unlucky.

Julian Thomas

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Aug 21, 1999, 3:00:00 AM8/21/99
to
In <qhzozms...@ruckus.brouhaha.com>, on 08/20/99
at 12:27 PM, Eric Smith <eric-no-s...@brouhaha.com> said:

>And what horrible calamity would happen if the service processor thought
>it was the wrong date (such a 1-JAN-1900)?

I suspect you don't want to know.

The first model of the 3090 had a service processor code bug that caused
the system to crash if it was running at year end - midnight local time.
The service support center saw the progression of calls from one timezone
to the next.



--
Julian Thomas: jt 5555 at epix dot net http://home.epix.net/~jt
remove numerics for email
Boardmember of POSSI.org - Phoenix OS/2 Society, Inc http://www.possi.org
In the beautiful Finger Lakes Wine Country of New York State!
-- --

There are 3 kinds of people: those who can count & those who can't.


Joe Morris

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Aug 23, 1999, 3:00:00 AM8/23/99
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jt5...@epix.net (Julian Thomas) writes:

>The first model of the 3090 had a service processor code bug that caused
>the system to crash if it was running at year end - midnight local time.
>The service support center saw the progression of calls from one timezone
>to the next.

If I recall the story correctly, the system had what some users called
the "E.T." feature: upon detection of a hardware fault the service
processor would automatically call an automated field service number
to report the details of the failure...and the year-end fault triggered
this code.

Joe Morris

Anne & Lynn Wheeler

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Aug 23, 1999, 3:00:00 AM8/23/99
to

and what is really wierd is the 3090 service processors were a pair of
(somewhat modified) 4361s running a highly modified copy of VM/370
release 6 (service panels were written in CMS IOS3270). Old VM
releases did have a problem switching DT/ST ... but never seem to have
had a problem with the year (unless this was some of the new service
processor specific modifications).

Julian Thomas

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Aug 23, 1999, 3:00:00 AM8/23/99
to
In <uwvumc...@adcomsys.net>, on 08/23/99
at 04:02 PM, Anne & Lynn Wheeler <ly...@adcomsys.net> said:

>Old VM
>releases did have a problem switching DT/ST ... but never seem to have
>had a problem with the year (unless this was some of the new service
>processor specific modifications).

I don't think this was a VM problem, just a specific bug in the SP code.



--
Julian Thomas: jt 5555 at epix dot net http://home.epix.net/~jt
remove numerics for email
Boardmember of POSSI.org - Phoenix OS/2 Society, Inc http://www.possi.org
In the beautiful Finger Lakes Wine Country of New York State!
-- --

Have you crashed your Windows today?


Darel

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Sep 12, 1999, 3:00:00 AM9/12/99
to
On Mon, 23 Aug 1999 16:02:17 GMT, thus spake Anne & Lynn Wheeler
<ly...@adcomsys.net>

>


>and what is really wierd is the 3090 service processors were a pair of
>(somewhat modified) 4361s running a highly modified copy of VM/370

>release 6 (service panels were written in CMS IOS3270). Old VM


>releases did have a problem switching DT/ST ... but never seem to have
>had a problem with the year (unless this was some of the new service
>processor specific modifications).

Its also interesting to note that the UK CAA uses pretty much the same
config as the FAA (except that now that IBM have declared the 9020 non
Y2K compliant people are going around trying to replace it with an
S/390 - even though the 4381's passed the Y2K tests)..

--
Darel Cullen Documentation is like sex when
Software Analyst It's bad, its better than nothing
London UK When its good - Its very good ;)

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