Visiontek GF4 Ti4200 Errors

I just upgraded my video card to a gf4 and now i’m experiences lockups/freezes/hangups with my games, namely counter-strike, warcraft3, ghost recon, and d2… i’ve got all the latest drivers and updates and all that, and i’m still getting this crap. i’m running an amd 650, 384mb ram, asus k7m mobo, sb audigy gamer, 300W power supply