2009-10-23 14:32

Here is how I configured dual screen under Debian unstable.


By default, the video card displays the same on both screens.

We first type the xrandr command to show the available video outputs.

Then, we issue the magical command:

xrandr --output DVI-1 --left-of DVI-0


  • If xrandr displays an error, add the Virtual parameter to the /etc/X11/xorg.conf file and restart X (see below).
  • Try --right-of if it’s inverted !

Xorg settings

And to set the changes permanently, we edit /etc/X11/xorg.conf:

Section "Device"
        Identifier      "ATI Technologies Inc RV380 [Radeon X600 (PCIE)]"
        Driver          "ati"
        Option          "Monitor-DVI-0" "Screen 1"
        Option          "Monitor-DVI-1" "Screen 2"

Section "Monitor"
        Identifier      "Screen 1"
Section "Monitor"
        Identifier      "Screen 2"
        Option          "RightOf" "Screen 1"

Section "Screen"
        Identifier      "Default Screen"
        Device          "ATI Technologies Inc RV380 [Radeon X600 (PCIE)]"
        Monitor         "DELL 1704FPT"
        DefaultDepth    24
        SubSection "Display"
                Depth           24
                Modes           "1280x1024" "1152x864" "1024x768" "800x600" "720x400" "640x480"
                Virtual         2560 1280
  • In the “Device” section, we list the different screen as “Monitor-OutputName”.
  • Then we put one section by screen, setting the second screen position.
  • The subsection “Screen > Display” must contain the “Virtual” parameter with a pixel area big enough to contain both resolutions.

Note: you can also try the graphical grandr frontend.

Gnome panels

You now have two screen under Gnome : a main one and a second.

If you want your panels on the other screen, just move them (right click on panel > Properties, uncheck Extend, move the panel, check Extend again).

I also suggest you to add another panel with a new window list on your second screen.


2009-10-23 14:32 · Tags: , , ,