Ari Pollak - Dual Head Projector

How to set up a permanently-attached monitor and projector using a Radeon X1050 dual DVI, Debian lenny, and X

This will make the projector start disabled, and you can switch between screens or use them side-by-side. Because the resolutions are so different between my monitor and projector, it doesn't make much sense to use them in clone mode simultaneously.

Edit xorg.conf

Replace your Device, Monitor, and Screen sections of /etc/X11/xorg.conf with this:

Section "Device"
    Identifier  "Generic Video Card"
    Driver      "ati"
EndSection

Section "Monitor"
    Identifier  "DVI-0"
    Option      "DPMS"
    Option      "PreferredMode" "1280x1024"
    Option      "Enable"    "true"
EndSection 

Section "Monitor"
    Identifier  "DVI-1"
    Option      "Disable"   "true"
EndSection

Section "Screen"
    Identifier  "Default Screen"
    Device      "Generic Video Card"
    Monitor     "DVI-0"
    DefaultDepth    24
    SubSection "Display"
        Depth       8
        Modes       "1280x1024" "1024x768" "800x600" "640x480"
    EndSubSection
    SubSection "Display"
        Depth       16
        Modes       "1280x1024" "1024x768" "800x600" "640x480"
    EndSubSection
    SubSection "Display"
        Depth       24
        Modes       "1280x1024" "1024x768" "800x600" "640x480" "720x480"
        Virtual     2560 2048
    EndSubSection
EndSection

Switch between modes

I set up hotkeys in my window manager for each of these commands to switch between display modes:

Enable the monitor and disable the projector:
xrandr --output DVI-0 --auto --output DVI-1 --off
Enable the projector and disable the monitor:
xrandr --output DVI-1 --mode 720x480 --output DVI-0 --off
Enable both the monitor and projector in dual-head mode, with the projector placed to the left of the monitor:
xrandr --output DVI-1 --mode 720x480 --left-of DVI-0 --output DVI-0 --auto