i'm currently using the DNA Force 1.0.7124 for my 6800gt and it's running great and i saw a bit of perfomance over the nvidia ones. you can even check other modified drivers.
Contrary to my sig, I am running zerOpoint 66.97 drivers. At the moment I am gaming for the eye candy, not the fps on benchies. If thats what you want I can highly recommend these.... decent performance but with the visuals to boot.!!! They can be gotten from guru3D.com, here is the link http://downloads.guru3d.com/download.php?det=983