I just got a used iMac G5 - it was my moms so I know it has been treated well. Everything was working for me, but it only had 768mb ram, so I replaced both sticks with 2 one-gig pc3200 ram (total ram 2gig). Everything booted up fine, and I was using the mac for about an hour before it grayed the screen and displayed a message saying I had to reboot - did it, and it came back up ok. I then started downloading software updates from apple, and about 30 secs into that the same thing happened (and it wasnt the software update requiring the reboot).

This time, it won't boot back up. When I push the power, I get the start tone, I get the gray screen with the apple, then the gear-like progress indicator comes on for about 10 seconds, and then the machine shuts down. This now happens every time I try to start.

I first tried reseating the new ram, but no luck. I then tried reinstalling the old ram, but no luck. I tried butting a leopard boot disc in, but it still crashed before trying to read the disc. I can't even boot to safe mode.

I did notice (after the fact) that the screw driver I used to open the case had a bit of magnatism. (screws would stick to it).

Any ideas? Bad/ruined ram? any other things I should try.

FYI - I'm a PC technican, but a complete and total newbie to a mac and the mac os. please be detailed in any help you can provide.