hey,

someone PLEASE help me w/ my problem. my daughter's pc has a mind of it's own. sometimes in the middle of the night it turns on by it's self and the shuts off. other times you'll boot it ok and while working it'll shut off, but if you bump it just right it turns back on again. i tried changing power cords and also changing power supplies. it's a win98se machine w/ a 2.3 g amd processor if that helps any.

With regard to switching on by itself, I have seen such phenomena ! Tends to be dodgy power but, if you've changed the PSU, I'd probably rule that out.

Check that your BIOS hasn't got any timers running. As soon as the PC switches on, keep pressing F2 until you get the blue BIOS screen up. Different BIOSes have different layouts but, somewhere, in one of the screens, you may find a Wake On Timer or similar setting with a date or time next to it. That could be switching it on. Is the PC networked? It might be activated by a communication from another PC using Wake On LAN.

With regard to switching off, again I'd say it's a power problem but you've already looked at that. If you load Windows and go into the Task Scheduler (often a little icon down by your clock), is there anything set to run at the same time of day that you don't recognise that could be the time that it keeps switching off?