4 ms·

People have a huge amount of trouble when using more than two monitors. I have two video cards and three monitors and I _just want to use all of them as a sing

People have a huge amount of trouble when using more than two monitors. I have two video cards and three monitors and I _just want to use all of them as a single desktop_. If I have two monitors, I can use TwinView and everything is great. When I add that third monitor, I have to use it as a separate xscreen, so it has it's own gnome panels and I can't drag a window over to it. If there is a solution, it's not obvious to me.

deleted 14y ago
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anoother 14y ago
Sounds like you're using the proprietary Nvidia driver? Set all your screens to 'separate X screen' and then check the 'Use Xinerama' box. You may have to set the correct screen offsets in the Nvidia control panel (or xorg.conf) after restarting X. I have this setup at work, and it works very nicely apart from the fact that only one of the two GPUs seems to be capable of displaying OpenGL content when connected in this way.
- michael_h 14y ago
  Yes, I'm using the proprietary drivers (for a variety of reasons, but CUDA support chief among them) and I had that exact setup for about five minutes. Using Xinerama forces compositing off, which makes for a less than snappy experience. I have three Dell 3000wfp's and without compositing turned on, the tearing is more than noticeable. I might be able to tolerate it, but I know that it is capable of working nicely (a la TwinView).
- mbell 14y ago
  > 'Use Xinerama' box Xinerama is old, buggy and more or less deprecated at this point. Also compositing doesn't work with it enabled which causes other issues.
  - anoother 14y ago
    > Xinerama is old, buggy and more or less deprecated at this point It is? What's the alternative?
    - mbell 14y ago
      Doesn't exist (yet). The intended replacement is multi-gpu support in xRandR but that feature has been pushed back release after release of xRandR for literally years now.
cbhl 14y ago
Does three monitors and two cards work fine under proprietary operating systems? I would expect symmetry at the least -- something like four monitors and two cards.

deleted 14y ago

[deleted]

anoother 14y ago

Sounds like you're using the proprietary Nvidia driver? Set all your screens to 'separate X screen' and then check the 'Use Xinerama' box. You may have to set the correct screen offsets in the Nvidia control panel (or xorg.conf) after restarting X. I have this setup at work, and it works very nicely apart from the fact that only one of the two GPUs seems to be capable of displaying OpenGL content when connected in this way.

michael_h 14y ago
Yes, I'm using the proprietary drivers (for a variety of reasons, but CUDA support chief among them) and I had that exact setup for about five minutes. Using Xinerama forces compositing off, which makes for a less than snappy experience. I have three Dell 3000wfp's and without compositing turned on, the tearing is more than noticeable. I might be able to tolerate it, but I know that it is capable of working nicely (a la TwinView).
mbell 14y ago
> 'Use Xinerama' box Xinerama is old, buggy and more or less deprecated at this point. Also compositing doesn't work with it enabled which causes other issues.
- anoother 14y ago
  > Xinerama is old, buggy and more or less deprecated at this point It is? What's the alternative?
  - mbell 14y ago
    Doesn't exist (yet). The intended replacement is multi-gpu support in xRandR but that feature has been pushed back release after release of xRandR for literally years now.

cbhl 14y ago

Does three monitors and two cards work fine under proprietary operating systems? I would expect symmetry at the least -- something like four monitors and two cards.