8800 GTS + AA = Stutter ?

[Mango]

I believe that the 8800 series has stuttering issues with certain games. It is a well known issue with UT2k4. IIRC, NVidia's recommended solution was to back down to an older driver (158.something??? I can't remember). Users have reported improvements in UT2k4 using that driver; however, weither or not it will help with Penumbra is anyone's guess.