Mark and BAP,
Here is what happened because I had it happen to me until I found out what it was.
ArVee and I talked about it briefly here earlier.
It is called CLOCKS, 2D clocks instead of 3D clocks.
Here: #msg-712819
When your video card goes into 2D clocking the points just fall off. Another interesting thing is the temperature is a lot cooler than when it is running in 3D clock mode.
The solution is to reboot the computer.
That seems to work Also, is that driver you are using good for Windows 7????
You need to check that if you have that card on a windows 7 machine.
You can check out driver 266.58 if you want to play with a different one that works also. It is a bit newer.
The best,
micro...