You may want to run "sudo nvidia-xconfig" to ensure that the GLX extension is in xorg.conf Then restart X.
If this doesn't fix it then "sudo gedit /etc/X11/xorg.conf" and ensure that Load "glx" Is inside Section "Module". Pricey -- glx info crashes after nvidia-glx-legacy install https://launchpad.net/bugs/84574 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
