constant rebooting

Hi everyone,

Well, this will be a good one for somebody. My windows 7 computer just started rebooting for no reason yesterday. I thought it was a hardware problem, so I took the drive out and put it in another computer, but it did the same thing. So, it must be a software or hard drive issue, right?

I put a brand new hard drive in and reinstalled windows and guess what? it did the same thing! I could not even get windows completely installed and it started to reboot over and over again. So, now I have two computers with the same problem. I have switched hard drives, and it makes no difference. How can it be a hardware issue on both computers? How can both systems be stuck in a reboot loop? Help!