what's so funny about 20 fps? Movies are only 24 fps, tv 29.9 fps
There is no need to achieve 128 fps, unless you play on some
fucked up engine like quake 3.
I usually always force it to top at 30 fps to reduce unecessary load on the video card and cooling system. Beyond that, your eyes do not see the difference.
10-20 FPS is a bit low for Q3, especially on a system to play INF which, usually, requires more video and computing power the Quake 3. Quake 3 and UT are pretty much two engines of the same generation. Both release in 1999 IIRC. Quake might be even a bit older then UT. Still, nothing to get all funny on