well try taking it out, because its gotta nick name "crash pack 2" and there is a reason for that, lol. its free so if sp2 isnt the problem put in back in. but im sure that it is. cause my games are kinda laggy like that on the higher settings, but my computer OS versios is SP2. so i have to deal with it. or it could be my vid card (look at sig) but at anyrate take it out and try the game and report back here.