Don't!!! That's about all anyone is getting. I have a squaddie with a HUGE system and the 9800 Pro. He's using regular Cat 3.7'S and doing the same as you are. It is also the same for me with my new 9600 XT and Omega's Cat 10's.
I have a 1.8 GHz, ABIT TH7-II mobo, 512 M of RDRAM. Everything's updated and tweaked. Having the 128 M on the Vid Card makes things smoother but infact I am wondering if I shouldn't return to my Gainward GeForce 3 Power Pak Golden Sampler.
I run VSYNC on and App preference on AA and AF D3D and the same for OGL but 2X AA. I went from 65 FPS in AH to 55, 45 to 35 in Forgotten battles, and we all know that AH2 has issues with the Radeon's.
On the plus....Perofmance in UT 2003, HALO, Call Of Duty, Max Payne, and MOHAAS have improved. Hehehe I don't play all of those on a regular basis.
The games run smoother (128M) prolly does that. Textures well a draw for me but, "Beauty is in the eyes.....of the Beholder"