So I was getting really bad framerates on my 9800gt so I rolled back my nvidia drivers from the 260.89 to the 258.96 and it made a huge difference !!! also im using the d3d9.dll fix as well but the driver roll back is what did the trick for me ...now to just fix the constant intermittent screen freezing !! which for some reason if i ctrl alt delete a few times it will kick me back to my desktop and then i can go back into the game which has reverted to the pause menu and i can start where i had frozen up at ...still its really annoying to have the screen freeze up so much ......hope this helps some people.

If its the same as F 3 i heard for my Nvidia GTX 295 then its back to 188.25 Driver.

yeah, this didn't work for me. rolling back actually made it worse. load times were increased along with stuttering. i am on a GT330M