Windows Me Keeps Re-booting!

Hey guys. I have an old computer that I just got, and I have been trying to get it up and running again. Its running Windows Me, dont know which version, and im having a problem, thats why im writing here duh. . Ok, any way, I get Me to boot up to where the windows sound comes on. When it goes here, Me restarts. I dont get any error messages besides that when Me starts up (right before the sound), windows scans the hard drive becuase of a bad shut down. Now, ive tried to re-boot into safe mode, but it does the same thing. Even custom boot up with almost nothing restarts itsself. Ive already done the recovery of Me with the disk, and re-installed Me, but it still restarts. Does anyone know what could be going wrong with windows? A software, hardware problem? Ive tried to google this but can not find anything that helps me. Everything in BIOS is up and running fine, or as it seems. As I said, I got this computer from a friend, so I do not know what all has been done. I believe its a custom built PC becasuse the bootup disk and recover disk has Lan-Plus on it.

Thanks to anyone who can help.

I say its the Power supply being that you said old. either that or bad ram.

other thought. Imagine how fast ME/98 would run if it can run a Quad-Core CPU.

Also look for bulged / leaking capacitors on the motherboard... you can install Windows until you're blue in the face and it won't make any difference if you've got some of those.