The NVIDIA 9x.xx drivers are utter garbage for me too. The SLI popup just set the tone. Control panel deadlocks the whole system, and is designed worse than ATI CCC (which is admittedly quite decent). It screws over a clean Windows install too (pci.sys is missing). It takes five seconds for the context menu for the system tray icon to appear. What the hell happened to NVIDIA's QA? I've never had so many problems. I want the 2 hours (reinstalling Windows) of my life back. The 8x.xx drivers were great. I miss the old control panel. All I want now is a conf file. I'm sick of these fisher price grandma interfaces running on .NET with miscellaneous stuff hidden on the side in the form of sentences that lag every time you click on something. The problem is, if I want all the video features (that they promised at the intro of the GF6 series), I need the 9x.xx drivers. argh...
Oh, did I mention I also got "out of range" on my monitor after upgrading to the first official WHQL 9x.xx drivers? I worked around it by going to safe mode and then next time I rebooted it was 60 Hz.