I guess you can try setting everything to zero as some items seem to start at zero ...

The clip plane is ususally the most important way to increase fps but you lose a lot of seeing far.

i would try this one first:

CVar_farclipoverride


Also maybe the bit depths and resolutions might same some computing power but I think with 32 bit systems its always to 32 bit percision but I am not sure:

gxColorBits - Color bits

gxDepthBits

And this one for sure:

gxMultisample

There seems a lot of good stuff to try:

horizonfarclip - Set draw distance for the horizon (terrain). When larger than farclip, will show 'shadows' of terrain in the distance.


Maybe someone could really up frame rates but using these commands.