Computer Reboots by Itself ?!?!?!?!?

[ADUBZ]

I recently built a computer for a customer & the customer tells me that when he leaves his computer (Its left on all night) and returns to it in the morning, he says that he noticed that it has rebooted by itself and I checked the system but I don't see anything wrong with it. It's specs are listed below:

AMD XP 2000+
512 PC133 SDRAM
40 GB HDD
128 MB Graphics

Its running MS Windows SE 98

Please help :-(
ADUBZ

 

[newbiepcuser]

Does it have motherboard resource/management software? You can check the voltage from withing windows and temperatures. You can also set it to record settings over night also?

Are you using an ECS board, I heard they are picky on RAM and powersupply.

 

[LesPaul]

Does it ever reboot on him while he's actually using it, or when he's around to see it? Sounds like it might be a power settings issue (BIOS or windows.. worth checking both), if it only happens during the night of inactivity.