Windows Xp Fps Limit?!?

Hey guys, I have an Athlon Xp 1700+, hercules 3d Prophet II Ti, and 19 inch Hitachi cm721F monitor. I have been curious about this, I am in a TFC Clan, And i play alllll the time, The problems seems as if Windows Xp has a limiter of some kind of the fps rate, i top out at 60 no matter what my hertz frequency, right now its set at 85Hz and still running 60fps at 1152x864. Anything i can do that someone may know that can help get my fps past 60?
Thanks
[WCA]Sk8tan -RC-