What Scotty says, what driver are you running? 66.00 ???? mate Noah used those on the ark, you don't need to wait until windows reinstall, just delete drivers from add/remove in control panel, run driver cleaner, then try the latest whql or if you're feeling adventurous try the 76.50, I have been running them for a month now with no problems. I have dual crt's on my Ultra (2x dvi adaptors) and everything runs fine on the second monitor. I am presuming you are using dual display in the nvidia control panel (if the 66.00's allow it, dunno I have never been that far back in history
lol)
Update today
Cheers