With the change of the way Ubuntu interfaces with its hardware (through FDI files), it took me a while to figure out how to change the default virtual desktop so that I could do extended desktop on my Thinkpad X60 tablet to use screens that are 1400 pixels wide or greater.
It turns out to be very straight forward:
Edit your /etc/X11/xorg.conf to have the following section:
Section "Screen" Identifier "Default Screen" Monitor "Configured Monitor" Device "Configured Video Device" SubSection "Display" Virtual 2840 1050 EndSubSection EndSection
So now when I encounter projectors/screens that are wider than 1024 pixels, I can still do extended desktop by using either the Fn+F7 key, or going to the System -> Preferences -> Display application.
Tags: thinkpad ubuntu