You higher you set the resolution you lesser can you set the refresh rate.
So if you set your resolution to like 800*600 you could set teh refresh rate to 100 or 120.
And btw flat screens can only take 75 hz.
Thats why CS pro gamers a playing with old CRT screens and with a resolution on 640*480 so they can feel the 100 fps
(if you have 100 fps and you screen can take 60 hz it only looks like its running with 60 fps)