From: John Stone (
Date: Thu Nov 17 2011 - 13:30:06 CST

  You didn't state what graphics driver you are using, but if you aren't
running the NVIDIA-provided drivers, that would be one of the first things
you should fix. If you're using the open-source drivers that ship with
ubuntu, you are surely bound to encounter various performance problems.
If you have the NVIDIA drivers installed, then please run this command
and tell me what it says, when you have 2 VMD sessions open and running:
  /usr/bin/nvidia-smi -a |grep -i free

  John Stone

On Thu, Nov 17, 2011 at 09:16:10AM -0800, lam nguyen wrote:
> Doing this way helps a little bit. I can open 2 windows and enlarge them
> without problem. But when I open the third one, my computer almost
> freezes.
> Lam
> On Wed, Nov 16, 2011 at 10:29 PM, Tristan Croll <>
> wrote:
> Lam,
> In that case, *definitely* try disabling the X11 Composite extension.
> sudo gedit /etc/X11/xorg.conf
> Then add to that file:
> Section "Extensions"
> A A A A Option A "Composite" "Disable"
> EndSection
> Cheers,
> Tristan
> From: [] On Behalf
> Of lam nguyen
> Sent: Thursday, 17 November 2011 2:21 PM
> To: Ajasja LjubetiA:*
> Cc:
> Subject: Re: vmd-l: VMD slows down at multiple windows
> I have VMD 1.9. I have tried running it on ubuntu, kubuntu and mint. I
> installed these three OS' to test which one I like most. I have VMD
> slows-down problem with all three systems. My Nvidia card is quadro FX
> 580. I don't think I run out of memory because I have this problem even
> right after restarting computer.
> Lam
> On Tue, Nov 15, 2011 at 1:08 AM, Ajasja LjubetiA:*
> <> wrote:
> Hi,
> I think you forgot toA mentionA some crucial information: Which OS are
> you running, what VMD version and which Nvidia card?
> so I don't thinkA power is the problem.
> Yes, if power would be the problem, the computer wouldA probablyA just
> reset. Perhaps you are running out of system or GPU memory?
> Ajasja
> On Mon, Nov 14, 2011 at 23:51, lam nguyen <> wrote:
> Hi all,
> There is an annoying VMD problem with my desktop. If I open several VMD
> windows, from the third one they slow down a lot. It is a new machine so
> I don't think the power is the problem. Because my 4 years old laptop
> can handle many VMD windows without slowing them down. I wonder if this
> has to do with Nvidia card?
> Is there anyone having the same trouble?
> Lam

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