When I shutdown windows, it just restart again and again..What's wrong w/ my PC?

Its a P-III 600Mhz CPU, WIndows XP Pro SP2.

When I shutdown windows, it just restart again and again..What's wrong w/ my PC?windows movie maker

It could be many things.... start by disconnecting your Hard Drive... if it still restarts and does not let you stay in the bios try a new Power Supply... if persist its most likely your motherboard... make sure to disconnect everything else...

When I shutdown windows, it just restart again and again..What's wrong w/ my PC?microsoft project internet explorer

u have virus i think
A program not properly installed or virus!