Oh, okay. To be straight, I have that game too and its very poorly coded as even its dated graphics cause issues on powerful rigs. Make sure you have the latest driver for your video card. Also, what are the specs of your system and what are you using for settings in the game?
Have you checked for any updates regarding the game? Silly question maybe, but I gotta ask it. I have a similar set up, although I am running SLI. Like I said, I have the game and would be willing to test it out for you if you like. Let me know specifically where you are seeing the graphic anomalies and I will download the game after I post.