Computer freezes... Could it be video card?

My computer is freezing up on me whenever i play StarCraft2 (and any other game for that matter). Once it freezes I turn it off and then back on. It then gets stuck at the windows XP loading screen.

If i let my computer sit for a few hours I will then be able to get back into xp(not all the time). Everything seems to work fine until i start playing a game(usually. sometimes it freezes even when im not playing anything but, for the most part, only when i'm in a game). I'm using a NVIDIA GeForce 8500 GT. ASUS M2N-E motherboard.

Any ideas what could be wrong?
(no onboard video card)
 
Back