When starting up my computer it freezes/restarts. I use Windows XP and I don't know what is going on. When I start up my computer it goes through all its normal functions through the start up phase. It loads my virus protection and all but a few seconds after it loads all of them up the computer will freeze and I see a red rectangle in the top left of my screen. My computer then restarts and it goes through this over and over until I turn off my computer. Any clue whats up?