Refresh rate?
Right click empty spot on the
desktop, go to properties.
Click the settings tab then advanced.
Now click the monitor tab and check the refresh rate.
You may need to try several like: 70mhz or 60mhz.
Also click setting to show only refresh rate monitor can handle.
If this does'nt help maybe one of our other members can help you.
Or try newer drivers for vid.
G'Luck