when i installed XP Pro SP2, i tried to intsall GTA San Andreas, but i couldn't, my PC immediately switches off, may be smth with power supply? i can't finish making my own movie, because of the same problem, what shall i do? I bought my PC 3 months ago, so it is not dusty, and it works perfect, only strange switches off! please, help me, what shall i do, reinstall my OS? i can't understand whats the problem, i play games, lithen to music, watch films, and everything is perfect, but.....switches off. Usually my PC switches off when i install some programme or game, or burn CD/DVD, it never switches off when i play games, or watch films. i have a lot of coolers in my system block, so, the temperature should be good, not hot at all!