Well, I can't say I was aware of that. I'm using these drivers 'cause I have a 6600GT and I need performance.

My current set is a modified 91.47.

Since the general concern about the modified drivers is their stability, I don't go for anything on the market. After having to dispose of my problemous Dhzer0point set, I decided on Z-Tweaked 91.47 reading that it's flawless and good at performance scales. And it really is so far.

Here it is. Checked. Clean.

You may search for options though. DriverHeaven hosts both Omega and Dhzer0point drivers.

Hope that helps.