At random moments in the game, missiles exploding, in the minigame where u are trying to get sponsored and are in the room where the spikes pop up etc my PC will just restart. No errors, nothin. Happened before the patch and after. my pc specs are...

quad core i7 2.8ghz, 4 gig ram, vista 64, geforce gtx580 OC watercooled

Do I need more ram? Could that be the issue? Any tips to help prevent this? thank you