So it reads to me like even with a clean install of these drivers, RivaTuner is still a tad unstable. I did do an upgrade install of 195.39 from 191.07 admittedly so I was going to try doing a clean install tonight. Don't think I'll bother now. Instead I'll monitor the feedback on these drivers first while I wait for newer official WHQL drivers. In my experience the WHQL drivers tend to be (but not always) less problematic overall. The 191.07 ones for example performed flawlessly in Vista.