[NewOldbie]

I've got two AGP G4's in front of me with the same problem, please chime in if you have any ideas.

The system will startup and run fine, but after a while I get the grey'ed out screen: "You need to restart your computer. Hold down the power button for several seconds or press the restart button." This happens regardless of what I'm doing. Sitting in the finder trying to go to preferences, launching programs, or using the web.

1 computer has an ATA drive, the other has SCSI. Both systems run the original 20 GB drives. Running Jaguar (10.2.6 and 10.2.8).

I have tried rebuilding a virgin system on two separate [firewire] drives. These firewire drives will run fine BEFORE being hooked up to the affected systems but once it has hitched on, they display the same symptoms (so it's not the IDE/SCSI controller).

I can't get Retrospect to run a backup of the affected drives (Internal consistency error -10) nor does disk utilities such as Diskwarrior or Drive 10 help. "unexpected error"

Between the two drives I've got about 25 GB of data that I need to preserve if at all possible.

Yesterday I even tried running a 17" ALbook as a startup disk but got nowhere. The built in CD/DVD drives will not allow me to start up with a CD (Jaguar CD/DVDs are also DOA).

Not much else I can do other than to swap boards and try and find a combination to get the suckers to work long enough to pull the information out. But this is just weird.

Would appreciate your suggestions.

[bonk]

I think this is a USB issue, I get it every now and then on my Dual 500 when I switch my KVM switch, which is also usb. But I remember somewhere reading something about it ...

[reader50]

Check your system fans, including the fan on the graphics card (if it has one). Your systems are old enough to experience fan failure, and overheating chips could explain most of your symptoms. They would start up and run fine for a while, then fail.

This would not explain the inability to boot from the optical drives, unless the ATA controller has suffered damage, or ribbon cables have worked themselves loose somewhat.

Check all the internal cables while you are at it. Reseat as needed.

[NewOldbie]

Thanks for the quick replies.

I just reset the PMU chip and the problem didn't go away.

I think I'll try swapping the drives next.

ATA or SCSI controllers going out wouldn't affect the firewire drives though would it? Or is there some other I/O manager on the logic board? If that is the case I doubt I could do anything other than replacing the motherboard.

Will check all the cables while I'm at it.

This happening to both computers within a 1 year period, what are the odds? I guess I should go buy a lottery ticket while I'm hot.