From: John Stone (
Date: Wed Dec 03 2014 - 15:11:44 CST

  The VMD output you have included below seems to indicate that
you're trying to run VMD using VirtualGL. The CUDA error indicates
that you're running VMD on a machine that has a very out-of-date
NVIDIA driver of some kind. You can check what the driver version is
like this:
  cat /proc/driver/nvidia/version

The next warning about the "Composite" extension is non-fatal, but
indicates that the X-windows configuration has the composite extension
turned on, and generally I would recommend that it be disabled because
it has a bad track history of interfering with stereoscopic display
and other advanced OpenGL features.

The final errors are the ones that are more serious. These errors appear
to be VirtualGL errors and they are complaining about being unable to load
an OpenGL software rasterization driver of some kind "swrast". It seems
that your system may have a set of mismatched OpenGL drivers being used by
VirtualGL and VMD, and that this is causing problems.

Can you comment further about how you are running VMD on this system?
All of those "VGL" messages you see are not part of VMD, they must have
to do with your particular host machine and its windowing system, and
I'm guessing they are related to VirtualGL.

  John Stone

On Sun, Nov 30, 2014 at 09:32:36AM +0100, Albert wrote:
> Hello:
> I've installed the pre-compiled CUDA-LINUX X64 VMD-1.91. in my computer,
> when I try to start VMD, it always failed with messges:
> Info) Molecular Dynamics', J. Molec. Graphics 1996, 14.1, 33-38.
> Info) -------------------------------------------------------------
> Info) Multithreading available, 8 CPUs detected.
> Info) Free system memory: 14928MB (93%)
> Warning) Detected a mismatch between CUDA runtime and GPU driver
> Warning) Check to make sure that GPU drivers are up to date.
> Info) No CUDA accelerator devices available.
> Warning) Detected X11 'Composite' extension: if incorrect display occurs
> Warning) try disabling this optional X server feature.
> libGL error: No matching fbConfigs or visuals found
> libGL error: failed to load driver: swrast
> [VGL] WARNING: The OpenGL rendering context obtained on X display
> [VGL] :8 is indirect, which may cause performance to suffer.
> [VGL] If :8 is a local X display, then the framebuffer device
> [VGL] permissions may be set incorrectly.
> Info) OpenGL renderer: Quadro K1100M/PCIe/SSE2
> Info) GLSL rendering mode is NOT available.
> Info) Textures: 2-D (16384x16384), 3-D (4096x4096x4096), Multitexture (4)
> [VGL] ERROR: in readPixels--
> [VGL] 374: GL_ARB_pixel_buffer_object extension not available
> It's very strange that my Pymol works fine in the same machine....
> Does anybody have any idea?
> Thank you very much.
> Albert

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