Riva TNT2 M64 problem with detonator 3

Hello, my name is RoldeR.
I have a riva tnt2 M64, in a celeron 500mhz and 64 mb of ram, and drivers detonator 3.
And the power of my riva dosen’t up the 50% but say the web of the nvidia.
Anithing person whit response this problem.