I have a Hannspree HF257 and I seem to have been having an issue for a while. I posted it on one of the other forums here, as well. I thought maybe it was my drivers at first or the fact that my card has 2 GPUs (it's one of the old, 275GTX CO-OPs) but now I don't think so...
When I try to set my resolution through the NVIDIA control panel rather than from the desktop, I lose a portion of my screen (it gets cut off). I didn't understand why until I went through the resolution settings from the desktop, clicked Advanced, Monitor and saw that my refresh rate was set to 59. When I tried setting it to 60, I had the same results.
Should I just get a new monitor? There are some games (though few) that actually get cut off because I cannot set the refresh rate below 60 for them.