Typical fault issues with the iMac G5

[cytherian]

I inherited a faulty iMac G5 from a family member. The "You need to restart your computer" forced dialog appears every now and then upon boot up or during disk accesses. It has 2Gb of RAM and the two DIMMs checked out OK with memtest, but only when run individually in slot 0. For some reason, both memory DIMMs installed together appear to increase the occurrence of faults. It does show signs of early capacitor leakage. A few of them have a dollop of beige powder in the center. None of them are swelling yet, though.

The hard drive is functional enough to serve as a slave, so all valuable data was copied from it. However, disk utility tests continue to crash at various points of testing out the hard drive. "fcsk -fy" found errors and couldn't repair them. I did a fresh "erase and install" of OSX 10.5, which went fine up to the 2nd disc, until it failed at the very end. The computer could still boot up OK, but when running the disk utility to check on things, the computer locked up again. Running the install once more only got through the 1st disc... very strange behavior. So, it looks to me like all this computer needs in the short run is a new hard drive, then later on a replacement of the capacitors.

Any other things to keep in mind on troubleshooting faulty G5's? Could there be other factors contributing to the unstable function of this G5? If so, please let me know what diagnostics or checks I can run to narrow down the problem(s). Thanks!

 

[cytherian]

Well, I went through a myriad of gyrations, testing this and experimenting with that... and I was finally able to re-install OSX 10.5 without a failure. I have one 1Gb DIMM in slot 0, because with the other one installed the G5 seemed to suffer crashes more frequently.

As it stands right now the G5 boots up OK and I'm able to use basic applications, but the Disk Utility presents some challenges. While it doesn't indicate any disk errors upon opening it ("Verify Disk" is disabled), I find that if I run a Verify on Disk Permissions that the system occasionally crashes. I have no idea why. SMART status is "Verified."

I saw 5-6 capacitors with some beige powdery discharge on the tops of the (+) vent markings, but no swelling. If these capacitors are operating below specification, would they be responsible for system instability? I'm trying to figure out at this point if it's the capacitors or the hard drive that might be responsible for all the havoc I've been experiencing with this computer.