The rest is redundant Intrepid Alpha 6 onwards :-). The standard interface works fine.
I have a VGA 19″ monitor and an LCD 19″. But how to get reliable dual monitor? The GNOME screen resolution interface has never been able to get dual monitor working properly. The closest I ever got on previous attempts was the screens the wrong way around!
A friend put me onto the following: HOWTO: Get Dual Monitors (“Dual Head”) to work on a Dell Optiplex 755 running Ubuntu 8.04 with Intel Q35 Chipset and Xorg RandR 1.2. And that did the trick in Ubuntu Intrepid Ibex Alpha 4 onwards.
Step 0 – No compiz sadly. It apparently doesn’t work above 2048 x 2048 and I want 2560 x 1024. So switch the effects to Off.
Step 1 – clean out /etc/X11/xorg.conf
sudo dpkg-reconfigure -phigh xserver-xorg
Step 2 – expand virtual desktop to size required for multiple desktops
Add the following subsection to the “Screen” section of xorg.conf:
Modes "1280x1024" "1024x768"
Virtual 2560 1024
I set Virtual to be twice the width of 1280 and the height of 1024. Now we are completely finished with xorg.conf. The rest is through xrandr.
The next steps were only required in alpha 4. In alpha 5 it worked with the two previous changes only.
Step 3 – Find out names of monitors
I found my two monitors were designated VGA-0 and DVI-0. Use your own names as appropriate in the following steps.
Step 4 – Set up as cloned first:
xrandr --output VGA-0 --auto --output DVI-0 --auto --same-as VGA-0
Step 5 – Now setup one large virtual desktop:
sudo xrandr --output DVI-0 --right-of VGA-0
Step 6 – run script automatically on startup:
See AddingProgramToSessionStartup for very helpful instructions.
xrandr --output DVI-0 --right-of VGA-0