:?: directx offer to change the direct draw refresh rate is that worth something performance wise :?:
More aboutdirect draw refresh rate override
If you're not stuck at 60Hz... I wouldn't worry about it. If you are, then increasing the refresh rate usually increases your max FPS. What's the point of rendering 125 FPS when your monitor is only displaying 60 FPS?
If you have the correct monitor drivers installed, just download RefreshLock. It will solve all your refresh problems. No more dicking around on a per- game/app basis.