Comments on: Ubuntu, NVIDIA and Two Monitors

By: morgauxo

morgauxo — Thu, 28 Jan 2010 21:50:54 +0000

Xinerama is great so long as you aren’t trying to use any 3D hardware acceleration. Xinerama and 3D do not play nice together. On some machines it might work thus some commenters here have Compiz and Zinerama but usually it does not. That’s probably why your Compiz broke.

Plain Twinview does get kind of weird when the monitor sizes don’t match. Mainly I think this is because it doesn’t make your desktop manager aware of the two monitors, it just assumes one big rectangle. This isn’t very nice because if you maximize something it gets split between the monitors which is probably not what you want. It’s also annoying because fullscreen apps (like games) will center themselves right in the middle, where the two monitors meet. If you try to look straight ahead you are looking at the space between instead!

Fortunately Twinview now has an option where it emulates Xinerama. I use Twinview that way and it works great. It’s just like Xinerama but my 3D stuff works.

One issue… XOrg or the nVidia drivers, I’m unsure which do not like having multiple applications using 3D at the same time. If I use 3D desktop effects like Compiz of KDE4 and start a 3D game it gets really slow, sometimes hardware acceleration is lost altogether and I need to stop X, unload the nVidia kernel driver, reload it and start X again. Or, more often I just reboot. This isn’t a multiple monitor issue though, it’s just a 3D issue in general.

Yes, it’s two years since the original article but someone searching for how to do multiple monitors might still read this and find it helpful.

By: Dual screens in Ubuntu - Monitor & Video Cards

Dual screens in Ubuntu - Monitor & Video Cards — Sat, 06 Dec 2008 11:58:50 +0000

[...] it selects the portable computer screen. OK, no laptop to test with. Check out this article – Ubuntu, NVIDIA and Two Monitors Start the terminal -> select nvidia-settings You have to have admin powers, it seems. You [...]

By: Bramlet

Bramlet — Thu, 04 Dec 2008 23:44:30 +0000

Does anybody know if its possible to set up dual monitors with one plugged into the vga port of the nvidia card and one plugged into the onboard video’s vga port? I am trying to hook up two crt’s and i dont have a dvi->vga converter handy.

By: Adam

Adam — Mon, 03 Nov 2008 04:17:40 +0000

I have twinview set up with two monitors of different sizes. You need to restart for the windows to maximize to one monitor.

By: Freelance Web Design

Freelance Web Design — Sun, 06 Jul 2008 17:40:36 +0000

Here’s a link to my xorg.conf file. I couldn’t get what I wanted out of the Nvidia-Settings.

I’ve got two monitors on one video card and a third on a second video card. It was a bit tricky but it all works really well. Twinview on the two on the same card, and a separate screen on the third (separate card).

Hopefully it’ll help.

http://phpfi.com/329606

By: Ryan

Ryan — Sat, 26 Jan 2008 08:13:17 +0000

I was reading on the urban terror forums that in order for this to work you have to have metamodes in xorg.conf so maybe that’s the issue anyway thought I would post the relative section for you or anyone else interested.

# Removed Option “metamodes” “DFP-0: 1680×1050 +0+0, DFP-1: 1280×1024_75 +1680+0; DFP-0: 1280×1024 +0+0, DFP-1: nvidia-auto-select +1280+0; DFP-0: 1024×768 +0+0, DFP-1: 1280×1024 +1024+0; DFP-0: 800×600 +0+0; DFP-0: 640×480 +0+0″
Identifier “Screen0″
Device “Videocard0″
Monitor “Monitor0″
DefaultDepth 24
Option “AddARGBVisuals” “True”
Option “AddARGBGLXVisuals” “True”
Option “NoLogo” “True”
Option “DRI” “true”
Option “XAANoOffscreenPixmaps” “true”
Option “TwinView” “1″
Option “metamodes” “DFP-0: 1680×1050 +0+0, DFP-1: 1280×1024_60 +1680+0; DFP-0: 1280×1024 +0+0, DFP-1: nvidia-auto-select +1280+0; DFP-0: 1024×768 +0+0, DFP-1: 1280×1024 +1024+0; DFP-0: 800×600 +0+0, DFP-1: NULL; DFP-0: 640×480 +0+0, DFP-1: NULL”
SubSection “Display”
Depth 24
EndSubSection
EndSection

By: Jim

Jim — Fri, 25 Jan 2008 01:06:15 +0000

Whoo hoo! I tinkered with things a bit more tonight. Twinview just doesn’t work for me – I think it’s an issue with the different monitor size/resolutions.

But I ended up UN-installing everything NVIDIA related from Synaptic. I then installed the nvidia-glx-new and everything it said I needed. A quick reboot and everything was working as before – I then enabled Xinerama and it worked. I just had to switch the xorg.conf to LeftOf and my screens are all setup and I can drag apps between monitors AND all my apps (Terminal / Gnome Do) work.

Though right now Gnome Do comes up on the left monitor and I’d like it to come up on the right but I can live with that for now :)

By: Ryan

Ryan — Thu, 24 Jan 2008 15:21:51 +0000

Maybe check directly in synaptic to see which version you have installed (nvidia-glx or nvidia-glx-new). I’m using new and if your card is supported perhaps upgrading to that will address the issue. By the way I don’t think 3D apps can work well (and definately not compiz) with xinerama because it disables dri. I came accross this when my little sister couldn’t play tuxcart because I had setup userful to let her and my brother both use the computer at the same time.

By: Jim

Jim — Thu, 24 Jan 2008 14:52:12 +0000

@Ryan – thanks for the info. You know I need to check and see if I have the latest restricted driver from Ubuntu. I’m not sure how to update those?? Hopefully I will have time over the weekend to tinker with this again.

By: Ryan

Ryan — Thu, 24 Jan 2008 14:36:21 +0000

Hi Jim, I just wanted to mention that I am running twinview having used nvidia settings and for me applications when maximised stick to the limits of each display under both metacity and compiz.

Gutsy Install with 8600GT and the 100.14.19 driver installed via restricted driver manager with a 20″ samsung and 17″ benq both running via dvi.