If X starts, but OpenGL causes problems, you most likely have a
problem with other libraries in the way, or there are stale symlinks.
See Appendix C for details. Sometimes, all it takes is to rerun
You should also check that the correct extensions are present;
'xdpyinfo' should show the "GLX" and "NV-GLX" extensions present.
If these two extensions are not present, then there is most likely
a problem with the glx module getting loaded or it is unable to
implicitly load GLcore. Check your X config file and make sure that
you are loading glx (see "Editing Your X config File" above). If your X
config file is correct, then check the X log file for warnings/errors
pertaining to GLX. Also check that all of the necessary symlinks
are in place (refer to the article titled "Linux - Installed components").