From: Brett Pemberton (
Date: Tue Jun 27 2006 - 18:57:15 CDT


The situation (as it has been explained to me by the VMD user) is that
he wishes to use vmd to interact with a namd job running on our cluster.
Since the compute nodes aren't accessible to his PC, he must ssh to the
head node of the cluster, and run VMD there, where it can talk to the
namd job.

The cluster head node is the machine with the ati card. His (and my)
machines both have nvidia cards.

VMD tells me

Info) Multithreading available, 2 CPUs detected.
Info) OpenGL renderer: GeForce FX 5200/AGP/SSE2
Info) GLSL rendering mode is NOT available.
Info) Textures: 2-D (4096x4096), 3-D (512x512x512), Multitexture (4)

This is the same, whether I use ssh X forwarding, or allow VMD to
connect to my X server remotely.


     / Brett

On Tue, 2006-06-27 at 17:15 -0500, John Stone wrote:
> Hi,
> In general it's not usually a good idea to run VMD through SSH,
> as the graphics performance will be terrible (independent of the
> other problems you're having). If you want to run remotely, I'd
> recommend using a normal X connection instead of tunnelling through
> ssh, if you care about speed and must display remotely. In the specific
> situation you've got, VMD should be detecting the ATI driver on
> the remote display and automatically limiting itself to prevent
> problems due to bugs in the ATI driver, but it's possible that
> this isn't happening for some reason. Can you send me the startup
> messages you get from VMD when it remote displays to the ATI box?
> If you're using the MESA ATI driver on the ATI box, that may be
> the source of trouble, but I should be able to tell from your
> startup messages what's going on there.
> Thanks,
> John Stone
> On Tue, Jun 27, 2006 at 03:52:41PM +1000, Brett Pemberton wrote:
> > Sorry for the semi-repost, but I've subbed to ask more about an email in
> > the archives.
> >
> >
> >
> > I'm experiencing the exact same problems, running vmd remotely over ssh.
> > Machine with VMD is an ibm e326, x86_64, running Fedora Core 5. Host
> > machine (fails on many) in my case, is an i386 running FC5 as well.
> >
> > The host machine has an nvidia card, with the nvidia drivers. The vmd
> > machine has an ati card with no 3rd party drivers installed.
> >
> > setting "VMDSIMPLEGRAPHICS 1" as suggested does work, however I'd like
> > to avoid that.
> >
> > Can you please advise how I can "change drivers", as mentioned in the
> > post?
> >
> > thanks,
> >
> > / Brett
> >
> >
> > --
> > Brett Pemberton - VPAC Systems Programmer
> > - (03) 9925 4899

Brett Pemberton - VPAC Systems Programmer - (03) 9925 4899