"Snow" usually means either your videocard is overclocked too high or is overheating. I'd go with the WHQL 12.41 drivers. They aren't the latest ones, but are well-known to be "a really good set".
Are you OCing your card? If so, set it to stock speeds. If not OCing, check to make sure that the fan on the vidcard hasn't died. Not out of the ordinary for this to happen.
I know nothing about the patch for the game. Sheesh, didn't the game just hit the stores a few days ago? They have a patch already? THat's a good thing, though!