From: John Stone (
Date: Wed Dec 11 2019 - 08:28:34 CST

  Sorry for my slow replies. I'm out of the office all week long due to
being selected for Jury Duty.

The current VMD 1.9.4 RTX test versions should run well on all recent prior
hardware versions (Pascal, Volta, Turing). I suspect that CentOS has a
broken driver distribution as it applies to OptiX, since there are now many
small driver components supporting OptiX that didn't previously exist.

I would suggest trying an NVIDIA-provided driver rather than a CentOS
provided driver on one of the machines in question and see if the problem
goes away.

Regarding OSPRay: No, actually OSPRay only uses the CPU presently.
  I do expect that future versions of OSPRay will exploit Intel Xe GPUs,
  but all existing versions of OSPRay are CPU-only and they are based
  on the lower level Embree framework, ISPC, and a few other libraries.

Best regards,
  John Stone

On Tue, Dec 10, 2019 at 09:35:12AM -0500, Giacomo Fiorin wrote:
> Hi Giulia, if it helps I'm running successfully the OptiX-supported VMD on
> CentOS 7 on a dozen workstations with different Intel CPU and NVIDIA GPU
> configurations. I installed the NVIDIA driver as part of the CUDA
> bundle, rather than separately. Admittedly the GPUs are based on
> Pascal-generation chips and not the more recent Turing like yours.
> To get more help, you may want to paste the output of nvidia-smi on the
> CentOS and Ubuntu systems, and also report whether OSPRay works: since it
> uses the graphics chip of the Intel CPU and skips the discrete GPU
> entirely, that should tell a bit more.
> Giacomo
> On Mon, Dec 9, 2019 at 6:00 PM giulia palermo
> <[1]> wrote:
> Dear VMD developers,
> we recently installed vmd-1.9.3 with cuda, OPTIX and ospray support on
> centos 7 systems (total 4 systems, 64 bit os, Intel Xeon, Nvidia rtx2060
> and rtx2080ti) via the module system. On all systems, the latest cuda
> version (cuda 10.1) is installed along with the latest display driver
> from NVIDIA. The startup of vmd also gives no errors. However, when we
> attempt to ray trace the loaded molecule, the option to use
> Tachyon+OPTIX is simply missing from the systems. Installing the latest
> vmd-1.9.4 alpha build locally have the same results.
> The issue that vexes us is that on an identical system with same gpus,
> cuda version but only ubuntu-18.04 64 bit LTS version, the Tachyon+
> OPTIX/ospray works.
> Can the developers please aid us in this matter to get the OPTIX ray
> tracing working properly?
> With warm regards,
> Giulia Palermo
> --
> Giacomo Fiorin
> Associate Professor of Research, Temple University, Philadelphia, PA
> Research collaborator, National Institutes of Health, Bethesda, MD
> [2]
> [3]
> References
> Visible links
> 1.
> 2.
> 3.

NIH Center for Macromolecular Modeling and Bioinformatics
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