DRI and libGL, libGLU
My DRI USED to work - and I did not change the XF86 server.
I am on Debian and have XF86 4.3 installed from Knoppix.
My system is a Thinkpad with the Radeon Mobility FireGL 9000 and Chromium was working great. I did something with the xlibmesa3-gl and xlibmesa3-glu or libglu1-mesa.
All the X startup suggests that agpgart and everything is OK. the glxinfo says:
direct rendering: No, yet glxgears works great. It's chromium and tux-racer that suck. AND THEY DID WORK --- something about the libGL that's wrong.