I ran a P96Speed and MAME benchmark between my Radeon 9000
and 9100, and as far as 2D, they were practically identical.

With Linux, surprisingly the 9000 was a tad faster handling
3D ops - exactly 350 glxgears compared to 328 with the
9100. (This is with a G3, BTW) My guess is the drivers
just work better with the 9000 ATM.