# glxinfo 
name of display: :0.0
Xlib:  extension "GLX" missing on display ":0.0".
Xlib:  extension "GLX" missing on display ":0.0".
Xlib:  extension "GLX" missing on display ":0.0".
Error: couldn't find RGB GLX visual

   visual  x  bf lv rg d st colorbuffer ax dp st accumbuffer  ms  cav
 id dep cl sp sz l  ci b ro  r  g  b  a bf th cl  r  g  b  a ns b eat
----------------------------------------------------------------------
Xlib:  extension "GLX" missing on display ":0.0".
Xlib:  extension "GLX" missing on display ":0.0".
0x21 24 tc  1  0  0 c  .  .  0  0  0  0  0  0  0  0  0  0  0  0 0 None
Xlib:  extension "GLX" missing on display ":0.0".
Xlib:  extension "GLX" missing on display ":0.0".
0x22 24 dc  1  0  0 c  .  .  0  0  0  0  0  0  0  0  0  0  0  0 0 None

>><<

 # eselect opengl list
Available OpenGL implementations:
  [1]   nvidia *
  [2]   xorg-x11


>><<

 # cat /etc/X11/xorg.conf|grep Driver
    Driver         "nvidia"

# cat /etc/X11/xorg.conf|grep glx   
    Load           "glx"