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olePigeon · Mar 10, 2009, 04:59 PM

OK, I've tried my usual troubleshooting ideas, I was hoping someone else here has a suggestion.

I have a Quicksilver Dual 1GHz G4 I really wanna get working, but it crashes almost always at the same time. On occasion, it'll boot most of the way then crash.

I tried zapping PRAM, resetting the PMU, I swapped RAM out, I reseated all the hardware including the CPU, etc. When I boot from the Hardware Diagnostic CD, all the hardware passes. However, sometimes it'll hang when trying to boot the Diagnostic CD, and sometimes it'll just die and fall into Open Firmware after just starting the test. As I just mentioned, when the test does run, it passes.

Any ideas? Hate to see this machine go to waste. Dual 1 GHz with 2GB of RAM, (used to) runs Leopard great.

reader50 · Mar 11, 2009, 04:34 PM

Got a spare graphics card around to swap in for testing? Check the GPU fan on your current card if it has one - ATi fans in particular seem to wear out after a year or two of cumulative running time.

Disconnect the internal HD and boot from CD. If the internal HD is getting flakey, it may lock up the system late in the boot process.

Unplug everything but keyboard, mouse, and monitor. It's possible network packets from the owned windows box in the next room is somehow tripping up your QS's boot process when the network drivers load.

olePigeon · Mar 11, 2009, 06:25 PM

Originally Posted by reader50

Got a spare graphics card around to swap in for testing? Check the GPU fan on your current card if it has one - ATi fans in particular seem to wear out after a year or two of cumulative running time.

Disconnect the internal HD and boot from CD. If the internal HD is getting flakey, it may lock up the system late in the boot process.

Unplug everything but keyboard, mouse, and monitor. It's possible network packets from the owned windows box in the next room is somehow tripping up your QS's boot process when the network drivers load.

When I try to boot from OS 9, it does crash at precisely the same spot. I'll see if I can find a different video card. This computer used to be our old server, so it ran 24/7 for a few years.

olePigeon · Mar 12, 2009, 12:55 PM

OK, I know it's not the video card.

Can a faulty power supply cause the computer to crash? On two occasions the machine just turned off completely by itself. I'm wondering if maybe there's a faulty power supply. That'll be my next experiment.

Crimson · 08:31 AM

A faulty PSU might indeed be able to crash the thing. If needed voltage is way lower than needed, the mobo doesn't have sufficient juice to run properly. HWD can run well, it doesn't boot the full OS and just might not need that much from the PSU.

Here's some info on the wiring: http://www.outofspec.com/frankenmac/wire.shtml
I'll need to make an adapter myself - I'll buy a PSU with 120mm fan later for my GigE...

Here's another resource on wiring: http://atxg4.com/gige-da.html
Found it out via Applefritter MDD power conversion article: http://www.applefritter.com/node/23857

olePigeon · Mar 14, 2009, 02:05 PM

Apparently we have 2 other Quicksilver G4s on campus, though I've never seen the other 2. I'll have to check each classroom and see if I can find them. I'm gonna just try swapping the power supplies between two machines.

If that doesn't work, then I'll assume it's the motherboard or processor. I'll try switching the processors between two machines. If that doesn't work I'll know it's a bad motherboard.

Crimson · Mar 14, 2009, 04:03 PM

Worth a shot, I'd say. But make sure the other QS' don't crash the way yours does first