From: Axel Kohlmeyer (
Date: Sun Mar 14 2010 - 14:11:16 CDT

On Sat, 2010-03-13 at 18:32 -1000, Irene Newhouse wrote:


> The only machine with a CUDA to which I have access is my husband's
> nearly brand new laptop, which runs Windows 7 & he's willing to let me

hmmm... unless your husband is a 3d graphics crazy gamer,
the nvidia chip will technically support CUDA, but whether
you see a significant speed increase is questionable. most
laptops have only very moderate GPU power (no surprise when
you consider the power consumption of high-end gear).

when you fire up VMD, you should see something like the
lines below, that will tell you want to expect.

Info) Detected 2 available CUDA accelerators:
Info) [0] Quadro FX 5800 30 SM_1.3 @ 1.30 GHz, 4095MB RAM, KTO,
Info) [1] Tesla C1060 30 SM_1.3 @ 1.30 GHz, 4095MB RAM, OIO,

this machine has two high-end GPUs, each with 30 multiprocessors of
v1.3 capability (i.e. a G200 or 1.3 capability type hardware) running
at 1.3 GHz. in zeroeth order approximation, you can assume that the
CUDA acceleration will go linear with the number of multi-processors
and clock rate. so if your GPU has only one multi-processor and runs
at half the clock rate, it is probably not worth it.

> tie it up for several days. Only now I can't get the ILS tcl file to
> run - all the selections are undefined, says VMD. I think it's because
> of those [expletive deleted] Windows paths that contain drive letters
> & folder names with spaces. Is there a way I can get VMD to process
> Windows folder names?

in principle there is. one has to do careful quoting of plain
strings containing spaces with {}. if you get errors about selections
being undefined, then it is likely that loading the molecules doesn't
work. so i would check where those filenames are defined and convert
the filenames to quoted ones.

let us know if that does the trick, so that the corresponding
VMD plugin can be improved.


> Thanks!
> Irene Newhouse
> ______________________________________________________________________
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Dr. Axel Kohlmeyer
Institute for Computational Molecular Science
Temple University, Philadelphia PA, USA.