computer hang

hi folks i hav nfS most wanted my pc config is as follws ram 4gigs,gygabyt G31 motherboard n win7 operatin syst. and Nvidia 9400 gt 1gb grafic card but still my pc is hungs somtimes durin iam playin da game plz need quick help

Hangs? Can you describe your problem better? What exacly happens? Does it lock up? Can you still ctrl+alt+del/alt+tab/whatever?

it just stops the game where it is well ican use alt+ctl+del only