OpenGl + Radeon + Win2k

Win 2K Pro
ATI Radeon 64mb DDR
Pentium 3 1Ghz
I am having severe OpenGl slow downs in all of my Games (Tribes 2, Halflife, ect). For some reason, ever since I installed DirectX 8.1 and Switched from an outdated Ati driver to the new presupported version (5.13.1.6043) with full OpenGL support. I am getting 70-90 less FPS (down from 100fps) in Halflife and Tribes 2 is slowing to less than 1 fps at times. Direct 3d works better, but not the same as OpenGL did before these modifications. I have tried installing older drivers and an older version of directx (after surgically removing it with directx buster), neither work. I did install my newer drivers correctly by uninstalling them beforehand. Also, I have downloaded Rage3d Tweak and have tried optimizing for performance and factory defaulting. Nothing works to get my FPS back up to 100. HOWEVER… Note this unusual fact. In Halflife when a weapon model is not displayed I get my FPS back up to 100. What the hell is going on???