[X4U] How can you diagnose a power supply problem?

[Mark Des Cotes]

Hi all,

I have an iMac G5 iSight that's been giving me problems. I started getting kernel panics on an increasing basis. Mostly on startup but sometimes once it was  up and running. It got to the point that I would have one every 10-15 minutes. Ran Disk Warrior, Safe mode, repaired permissions, ran hardware test, everything said the computer was fine. Yesterday morning it wouldn't wake from sleep. Shut it off via the power button and tried to restart it, fans came on and the white light on the front lit up but nothing else. I couldn't hear the HD and no response from the DVD drive when I try to insert a disk. After a few minutes the fans sped up but that's it. Tried a few more times with the same results. 

I opened the iMac up (thank you YouTube) and removed the HD and put it in an external enclosure I have. It works fine. I'm able to access it from my wife's MacBook. I made a clone of the drive to be safe. I put it back into the iMac and got the same results as before. I now know that the HD works so I'm thinking it's something else. My guess is the power supply but I'm not sure as I've never had one go on my before. Could it be that the PS has enough juice to run the fans & light but not the HD or optical drive? I thought that when a PS went nothing wold work.

Any and all help is appreciated.

Mark Des Cotes
Owner-Graphic Designer
Marksman Design

Mailing address: 
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