Ubuntu – How to extend display with two monitors

Spent a lot of time researching how to do extend my desktop onto a second monitor in Ubuntu 11.04 with Unity. Extending the display and desktop is a simple task on Windows but under Ubuntu it was very difficult until I found the right software, disper.

I’m using an EVGA NVIDIA GeForce GTS 450 graphics card. I used the official NVIDIA drivers and the NVIDIA X Server Settings program. The best configuration I could achieve, was a separate instance of X Windows on each display. The only issue was I couldn’t move applications between them, which turned out to be a hassle as I’m used to moving windows/applications back and forth.

I ended up setting my NVIDIA X Server to clone the display on the second monitor. When I boot into Ubuntu classic w/o Unity, the second display automatically becomes an extended desktop. This would have been my final solution except I had already become accustom to using Unity. When I would boot into Unity, each display became an individual X server.

There is an application, disper, which cleared up all my issues. Now, when I boot into Ubuntu with Unity my displays are cloned. I open the terminal and type disper -e, which automatically detects the max resolution on the displays and extends my desktop!

The commands to grab disper and a nice disper indicator to fit in the top menu bar of Unity:
sudo add-apt-repository ppa:disper-dev/ppa
sudo add-apt-repository ppa:nmellegard/disper-indicator-ppa
sudo apt-get update
sudo apt-get install disper disper-indicator

If you want to allow disper-indicator to start every time Ubuntu starts, the directions are very simple on Ubuntu 11.04:
Go to System Settings (located at the bottom of shutdown button menu)
Open “Startup Application”
Click the Add button and type “disper-indicator” without the quotes in both name and command fields. Click the Add button and then Close.
On the next reboot the indicator will automatically be started!

It works great for me and hopefully this will save some time searching for an extended display solution using an NVIDIA card on Ubuntu 11.04 with Natty.

Some helpful resources I found along the way:
http://ubuntuforums.org/showpost.php?p=10858752&postcount=22
http://ubuntuforums.org/showpost.php?p=8586619&postcount=8
http://www.ubuntuvibes.com/2011/06/disper-indicator-easily-clone-or-extend.html
Nouveau-Open Source Nvidia Drivers – Didn’t end up using this
Keyboard Shortcut to Restart X Windows
Setting up Ubuntu with Dual Monitors – Didn’t work for me
Comments on how to start disper-indicator on boot