Windows XP install shuts my computer off.

Hi, I was wondering if someone has had this problem before or could offer advice.

I am trying to install a new copy of windows on a newly formatted drive. Every time it gets to the "installing devices" section it gets to 34% and then my display turns off and on, continues installing for about 5 more seconds and then my computer shuts off. If I try rebooting, it will restart the installing devices procedure and then exhibit the same behavior.

I have tried multiple times installing windows and reformatting the drive and it continues to do this at 34% during the device install process. I have checked my cpu temp in bios during startup, and my cpu never gets above 47 degrees Celsius. I have swapped out memory modules to see if I had faulty memory. I have tried switching video cards, and nothing works. Any help on this issue would be appreciated as I cannot think of what else could be the problem.

My System Specs are:
Asus P4C800 Deluxe Motherboard
2.8 ghz P4 Prescott w/ 1mb L2 cache
(2) 1gb Kingston pc3200
500w Thermaltake Purepower
38 gb Seagate IDE
(2) 250 gb WD Cavier SE16 SATA drives
Radeon 9250 Pro PCI graphics card.

Thanks I'll try that. I had started to suspect it might be the power supply after checking out the Asus forums for this board, and reading about people having similiar problems where the power supply was at fault.