From: Josh Vermaas (
Date: Thu Jan 22 2015 - 08:00:34 CST

Hi Alexandre,

What information does VMD spit back at you at startup? This is (part of)
what the terminal spits back at me:
Info) VMD for LINUXAMD64, version 1.9.2 (December 31, 2014)
Info) Email questions and bug reports to
Info) Please include this reference in published work using VMD:
Info) Humphrey, W., Dalke, A. and Schulten, K., `VMD - Visual
Info) Molecular Dynamics', J. Molec. Graphics 1996, 14.1, 33-38.
Info) -------------------------------------------------------------
Info) Multithreading available, 24 CPUs detected.
Info) Free system memory: 28243MB (70%)
Info) Creating CUDA device pool and initializing hardware...
Info) Detected 1 available CUDA accelerator:
Info) [0] GeForce GTX 980 16 SM_5.2 @ 1.22 GHz, 4.0GB RAM, KTO, AE2, ZCP
Info) Detected 1 available TachyonL/OptiX ray tracing accelerator

Those last 4 lines are the important part. VMD needs to detect the
available cuda devices. If you don't see lines similar to those,
TachyonL/OptiX ray tracers won't be available. There are many potential
reasons why. The first thing I'd check on ubuntu is that you've
installed the appropriate libcuda package to go along with your driver
(eg. libcuda1-331 with nvidia-331). The second would be if your graphics
card is supported by the driver. For instance for the 980, the minimum
driver version needed for all of the functionality is the 343 driver,
which isn't in the default Ubuntu repositories, and I needed to install
it straight from NVIDIA's website. What specifically is the output VMD
gives you at startup?

-Josh Vermaas

On 01/22/2015 04:56 AM, Alexandre Suman de Araujo wrote:
> Hi all.
> I have an Nvidia card with CUDA support and installed the latest
> nvidia drivers in a linux ubuntu 14.04 machine.
> I downloaded the new 1.9.2 version of vmd (LINUX_64 OpenGL, CUDA,
> TachyonL-OptiX binary) and installed following the standard instructions.
> When I open the "Render" windows TachyonL-OptiX is not in renderer list.
> Can anyone help me?
> Cheers
> Alexandre