I can't help, try reading the thread above: but above all, can you confirm you are experiencing the problem with this game only? I am asking because this doesn't seem related to the game itself to me.
So far just this game.
Trust me, when it happened I checked EVERYTHING! :P
Looks like I got it.
I had ALL OF THE advanced graphics options tricked out. I don't know what did what, but I turned a few off I didn't think I'd miss and that seemed to clean everything up.
Somehow I'm not surprised. I looked around on line and at seems a lot of this enhancements weren't put together really well and could cause problems for people regardless of how good their PC is.