Originally Posted by CDE_1246
This may help. Im not running on 64-bit but it may have the same issue. In XP i ran on 4x antialiasing and i had the same problem with css when i upgraded to vista. I went into the nvidia control panel and forced 4xAA for css and i started it back up and my fps increased significantly, basically just like it was with XP. Hope this helps good luck!
BTW: Your running on the same video card as me! So this should work.
what kind of sound card do you have? wonder if that's whats doing it.