Here is tenmillion benchmark program originally written for SGI. you can get it from http://www.evl.uic.edu/pape/CAVE/linux/speed/
and also compare your results there.
It would be great if you can post your results here to help diagnose the problem.
I was hoping this program might assist in finding the performance problem with the drivers for MX cards on some systems. With this program the results of GF2 mx came out correctly compared to the TNT. with area=3 23Mtri/s and 4Mtri/s respectively. On the other hand TNT runs faster with glxgears and same performance to GF2 mx with other apps. This is really weird. May be to do with the AGP driver whether Nvidia or agpgart? don't really know.