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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
to
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
to
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

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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

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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

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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

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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