Here is how I configured dual screen under Debian unstable.
Xrandr
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
Notes:
- If
xrandrdisplays an error, add theVirtualparameter to the/etc/X11/xorg.conffile and restart X (see below). - Try
--right-ofif 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"
EndSection
Section "Monitor"
Identifier "Screen 1"
EndSection
Section "Monitor"
Identifier "Screen 2"
Option "RightOf" "Screen 1"
EndSection
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
EndSubSection
EndSection
- 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.


