• Hello MLAers! We've re-enabled auto-approval for accounts. If you are still waiting on account approval, please check this thread for more information.

G4 Digital Audio PS

I recently bought a couple of Digital Audio G4 PowerMacs for small change. One of them was a dual G4 533MHz, which I promptly got running Leopard Server (via Leopard Assist) for testing purposes. The dual DA runs it rather well, which surprises me, as the "real" installation that I administer at work runs on a Mac Pro. I am perfectly sure that the Mac Pro would scale better than the G4, but for light use, I can't really say that there is an obvious difference between the two machines.

The other Digital Audio is a 733MHz single G4, which I turned to just yesterday after finishing up with the first machine, with the idea of installing FileMaker 9 for hosting various files in a single location (so as to access them remotely from three other working machines). It could sleep when not in use — the beauty of the early G4s for such purposes being that they only draw about 8w while sleeping, which is about the same as when turned off altogether — and be woken up using a WoL script as needed. They also apparently idle at about 80w-120w, depending on the model. Cushtie.

It was an irritating unit from the start, however, because of fan noise, and I almost gave up, thinking that this must be the sort of thing that people complain about when they complain about G4s being noisy. However, I just discovered to my horror that the Power Supply fan has seized, which is a little surprising, because there is very little dust in the unit, meaning that it has not had that much use.

The PS, obviously, has been overheating, and though the main case fan tries to compensate, making a fair whack of noise in the process, it does not manage to push enough air through the machine to cool the PS adequately. I have no idea how long the machine ran like this before I got it, but it has run like this in my hands for an hour or two. Thankfully, there was no great load placed on the PS during that time; it ran without shutting down or exhibiting any symptom other than making a racket, so maybe it is still good.

It transpires that I have a scrapped AGP graphics machine, the case of which I have turned into a RAM/ Nubus & PCI card/ assorted crap cupboard in my "man cave" (that G4 case proved a rather elegant solution to this Mac collector's clutter problem, if I do say so myself). This means that I can probably salvage a replacement PS fan from the AGP Graphics machine (the PSs in the two are apparently incompatible, so they cannot be straightforwardly swapped).

Now, here's the issue: the scrapped AGP graphics machine had a lower-rated PS than the DA (200w versus 330w or some such). Should the fans still be compatible? I would have thought so, as one 80mm fan is more or less like any other, but I thought I'd best double-check. I'd rather not burn the house down, and this thing will run unattended (if mostly asleep) for maybe the next three or four years.... I would, obviously, lubricate the replacement fan before installing it.

 
Well, I got an hour or so unexpectedly in which to do this, and it transpires that the two fans had the same model number. Question answered.

 
But now the PS fan won't stop, even when the machine is asleep. Zut alors!

Zapped pram, made no difference.

I think I may now understand why the old fan burned out!

EDIT:

Removed SCSI card (had intended to install a couple of 18GB scsi drives in a RAID) and all is now well.

 
I have a problem with the fan in my g4 Quicksilver. It will spool up the fan during sleep at regular intervals.

There is a composite vide capture card installed, do you think removing it as you did your SCSI card will remedy this problem? I guess its worth a shot.

 
But now the PS fan won't stop, even when the machine is asleep. Zut alors!
As I understand it, there are at least two modes of sleep on these machines: deep sleep and "light" sleep. in "light" sleep, the fans don't go off, whereas in deep sleep, everything goes silent. I don't know why this is, I just know that it... is.
I have found this to be a problem under OS 9 when I have a USB card installed. Presumably because OS 9 doesn't understand USB 2.0, it complains that the card is preventing the computer from sleeping properly. The same computer with the same USB card sleeps just fine under OS X 10.4 and up, so it's probably a software issue. Since USB 2.0 drivers don't exist for OS 9 (yet?), this is a problem with no solution, other than running OS X instead for full sleep capability.

So perhaps this is what you discovered.

EDIT:Removed SCSI card (had intended to install a couple of 18GB scsi drives in a RAID) and all is now well.
Apparently that SCSI card isn't supported by the computer somehow. Do you know exactly what make/model of card? Perhaps you can find one which is more fully compatible (perhaps an Apple-OEM card?)
I think I may now understand why the old fan burned out!
It could be, or it could simply be that the fan was defective and died early.
I hope this helps...

c

 
Back
Top