PowerMac G4 MDD has power-on problems

[Tyrone F. Horneigh]

I have a G4 Mirror Drive Door that has trouble powering on. When it
does power on, it will run for as many hours or days as I need it to
run, leading me to believe that the power supply is OK.

But when I shut it down, it generally will not power on again until some
number of hours has passed. 6 hours, 10 hours, whatever it is. It will
eventually power on again and work fine.

When it fails to power on, the power light will either do nothing or
come on briefly when I press the power button.

I have reset the PRAM (Command, Option, P, R keys on boot up). I have
reset the NVRAM (Command, Option, O, F keys, then reset-nvram,
set-defaults, reset-all at the command line). I have reset the CUDA
button, replaced the 3.6 volt battery, re-seated the main power supply
connector on the motherboard.

Nothing has helped.

Does this mean that the power supply is in fact flaky? The
motherboard? Have I missed something else?

This is a maxed out MDD G4, with dual 1.25 gHz CPUs, 3 hard drives, 2 GB
RAM, OS X 10.4.11 on one drive, OS X 10.5.8 on another and MacOS 9.2.2
on the third.

Please excuse if this is the wrong newsgroup, but this one is definitely
the most active, and seems to have quite a collection of Mac experts.

Any help greatly appreciated.

[Tyrone]

In article <0001HW.203046430...@news.individual.net>,
Percival John Hackworth <p...@nanoworks.com> wrote:

> On 10-Feb-2018, Tyrone F. Horneigh wrote
> (in article<P86dnRmiY7r_W-LH...@supernews.com>):

> It's your call on if you want to buy a power supply and replace the existing
> one just to see if it fixes the problem, but a machine that hold isn't worth
> much. And parts for it will be expensive when you could be investing in a
> newer system that can run newer version of the OS and software.

I already have a newer system, a 2014 mini. 3 gHz i5, 8 GB ram, 500 GB
SSD internal, 1 TB external USB 3 drive, 10.11.6 and 10.13.3. It runs
fine.


> I manage to
> get 7 years out of my systems before a recycle them then move on to something
> newer. Ask yourself why you're keeping this thing running and if it's worth
> spending money on to fix. If so, how much? At some point, you'll decide
> that's enough and move on. Otherwise, buy the parts if you can find them and
> try to fix the system.

Its worth keeping just because it IS so old. If this was my only Mac,
then yes it might be time to move on. However, this is my fun Mac,
where I can boot up 9.2.2 classic in OS X 10.4.11 and run some really
old stuff, just for the hell of it.

Anyways, its working again, and I am typing on it now. I'll probably
send the power supply off to be repaired/refurbished. No point in
getting another 15 year old used one.

[Your Name]

On 2018-02-11 09:37:07 +0000, Percival John Hackworth said:
<snip>

> I manage to get 7 years out of my systems before a recycle them then
> move on to something newer.

<snip>

A whole seven years?!? Wow, you're on the cutting edge.

I got nearly 20 years of daily use, for both running my own
computer-work business and for leisure time, out of my beige G3 before
it died. :-(

[Lewis]

In message <P86dnRmiY7r_W-LH...@supernews.com> Tyrone F. Horneigh <nu...@business.net> wrote:
> I have a G4 Mirror Drive Door that has trouble powering on. When it
> does power on, it will run for as many hours or days as I need it to
> run, leading me to believe that the power supply is OK.

That is not a reasonable assumption. The largest draw for the PSU is
generally at power-on.

> When it fails to power on, the power light will either do nothing or
> come on briefly when I press the power button.

> Does this mean that the power supply is in fact flaky? The
> motherboard? Have I missed something else?

I'd guess the PSU is the issue. A replacement PSU for that machine is
pretty expensive (more than the machine is worth), but you might be able
to find one cheaper on fleabay.

You would need a 400W ACBEL unit. New they go for $200-250, I've seen
used ones on fleabay for about $100. I wouldn't spend that much money on
a G4 when I could get a much newer computer for the same price.

--
In the 60's, people took acid to make the world appear weird. Now the
world is weird and people take Prozac to make it appear normal.

[nospam]

In article <slrnp821dd....@Snow.local>, Lewis

<g.k...@gmail.com.dontsendmecopies> wrote:

> You would need a 400W ACBEL unit. New they go for $200-250, I've seen
> used ones on fleabay for about $100. I wouldn't spend that much money on
> a G4 when I could get a much newer computer for the same price.

or another powermac g4 for less.

[Tyrone F. Horneigh]

On 2/11/18 10:10 PM, Lewis wrote:
>
> You would need a 400W ACBEL unit. New they go for $200-250, I've seen
> used ones on fleabay for about $100. I wouldn't spend that much money on
> a G4 when I could get a much newer computer for the same price.

Used are $50 on eBay these days. I can get mine refurbished for $75.
It is indeed a 400W AcBel.

I will be going the refurbish route, as it makes no sense to get another
used one that is also going on 15 years old. Plus, I don't need another
new computer, I have lots of those - Windows and Mac. This is my old,
fun time Mac, with lots of old stuff that I wrote many years ago, along
with emulators for other old machines. $75 is fine with me.

IAC, I had it running all day today. It always powers on, eventually. I
figured the PS was going. The whole point of my question was to see if
I had missed anything simple.

[Lewis]

Good point, I didn't think of that.

--
WORDS IN THE HEART CANNOT BE TAKEN --Feet of Clay

[ErikRS]

Your Name wrote:
> On 2018-02-11 09:37:07 +0000, Percival John Hackworth said:
>> I manage to get 7 years out of my systems before a recycle them then
>> move on to something newer.
>

> A whole seven years?!? Wow, you're on the cutting edge.
>
> I got nearly 20 years of daily use, for both running my own
> computer-work business and for leisure time, out of my beige G3 before
> it died. :-(

Well, I still have my good ol' and fully working PowerBook 165 from 1993
and sometimes power it on just to see how good and fast it was.

OK, the battery and PRAM-battey are dead and I don't want to replace
them because they are horribly expensive, - but it works.:-)!

Hereto I have a 2002/03 PM G5/1,8ghz Dual with 4gb RAM running 10.4.11 +
9.2.2 and 10.5.8, a 2005 (prod. febr.2006) 17" PowerBook G4/1,67ghz with
4gb RAM also 10.4.11 + 9.2.2 and 10.5.8.

I use these two for running some applications that I don't have or won't
upgrade + some discontinued OS 9.x programs for converting old files etc.

For main work I now use two MacPro1.1 - a 4x2,66ghz (2007) and a
4x3.0ghz (2007, prod. jan.2008) each with 24gb RAM - both running 10.6.8
+ 10.7.5. The MP3,0ghz is also running MS Windows 7 Pro Ultimate with
all language kits installed...

I sure don't intend to replace any of them as long as they are working
that great... OK, if someone comes around and gives me a maximized
MP5.1, I'll think it over.:-)

Cheers, Erik Richard

--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Erik Richard Sørensen <mac-d...@MOVEstofanet.dk>
NisusWriter - The Future In Multilingual Text Processing - www.nisus.com
Openoffice.org - The Modern Productivity Solution - www.openoffice.org
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[ErikRS]

Tyrone F. Horneigh wrote:
> I have a G4 Mirror Drive Door that has trouble powering on. When it
> does power on, it will run for as many hours or days as I need it to
> run, leading me to believe that the power supply is OK.
>
> But when I shut it down, it generally will not power on again until some
> number of hours has passed. 6 hours, 10 hours, whatever it is. It will
> eventually power on again and work fine.
>
> When it fails to power on, the power light will either do nothing or
> come on briefly when I press the power button.

To me it looks to be the same problem I also had with a similar MDD
model. Suddenly it wouldn't boot and I tried exactly the same process
you already have done. - Nothing helped... - And also here, sometimes it
would boot.

I sold it for a few dollars. Some weeks later he contacted me to tell me
that it was the PMU (Power Manager Unit) chip that failed - i.e. a
condensor sometimes dropped out when it was warm. He replaced the
condensor with a similar one, and the MDD booted again without problems.

So it may be the same problem you have...

Chers, Erik Richard

[Tyrone F. Horneigh]

In article <P86dnRmiY7r_W-LH...@supernews.com>,

"Tyrone F. Horneigh" <nu...@business.net> wrote:

> I have a G4 Mirror Drive Door that has trouble powering on. When it
> does power on, it will run for as many hours or days as I need it to
> run, leading me to believe that the power supply is OK.
>
> But when I shut it down, it generally will not power on again until some
> number of hours has passed. 6 hours, 10 hours, whatever it is. It will
> eventually power on again and work fine.
>
> When it fails to power on, the power light will either do nothing or
> come on briefly when I press the power button.
>
> I have reset the PRAM (Command, Option, P, R keys on boot up). I have
> reset the NVRAM (Command, Option, O, F keys, then reset-nvram,
> set-defaults, reset-all at the command line). I have reset the CUDA
> button, replaced the 3.6 volt battery, re-seated the main power supply
> connector on the motherboard.
>
> Nothing has helped.
>
> Does this mean that the power supply is in fact flaky? The
> motherboard? Have I missed something else?
>
> This is a maxed out MDD G4, with dual 1.25 gHz CPUs, 3 hard drives, 2 GB
> RAM, OS X 10.4.11 on one drive, OS X 10.5.8 on another and MacOS 9.2.2
> on the third.

For all the millions - OK 3 people :-) - who have been left wondering
about this, I am happy to report that it was the power supply. I
removed it and had it fixed. There is a guy on eBay that refurbs them.
The MDD G4 is now running fine.

While I had it opened up, I added a spare 500GB drive I had lying
around, blew out lots of dust and cleaned the fans. It is not nearly so
noisy as before.

Good times.