ok, since your chip has no hardware support
try this
its called 3danalyser, it'll emulate the calls required to let you play games by forcing them through the cpu
http://www.falconfly.de/downloads/3danalyzer-v236.zip
this will be slower, and i can't promise anything
but by using this program i was able to get halo to work like it should do
they disabled the cloaking effect on the NV3x series where as they leave it working on the R3xx series
using this program i was able to fool halo into thinkin my card was a Radeon 9800pro and it enabled the full cloaking effects
this program is also used on 3dfx cards to emulate the missing features
(including Hardware Transform and lighting)
