Dual monitor setup: xrandr versus xorg.conf

Question

Dual monitor setups on GNU/Linux are known to be great fun! After fiddling with my xorg.conf for a couple of days, I've managed to come to a point where I can get pretty much what I want (two screens next to each other, windows draggable from one screen to the other) by starting up X, and then manually calling:

xrandr --output CRT2 --right-of DFP2

I'm using RandR 1.3 because Xinerama does not work for my setup (and seems to be obsolete in a way, too).

According to this website, I should be able to achieve the same effect statically through my xorg.conf - however, I don't seem to get it working correctly.

I'm using the fglrx driver for my ATI card, GNOME 2.32.1, and here is my xorg.conf:

Section "ServerFlags"
    Option      "RandR" "on"
EndSection
Section "Device"
    Identifier  "Device"
    Driver      "fglrx"
    BusID       "PCI:1:0:0"
    Option      "Monitor-DFP2"      "Monitor0"
    Option      "Monitor-CRT2"      "Monitor1"
EndSection
Section "Monitor"
    Identifier      "Monitor0"
EndSection
Section "Monitor"
    Identifier      "Monitor1"
    Option          "RightOf"       "Monitor0"
EndSection
Section "Screen"
    Identifier      "Screen"
    Device          "Device"
    Monitor         "Monitor0"
    DefaultDepth     24
    SubSection "Display"
        Depth     24
        Modes     "1920x1080"
        Virtual   3840 1080
    EndSubSection
EndSection

To me, this looks pretty much like the setup recommended on the aforementioned website, however, I will simply get the same image in both monitors. Again, I can call xrandr afterwards to achieve the desired effect.

Any ideas how I can fix my xorg.conf?

Solution 1

You forgot a "Monitor" entry in the Screen section.

See below:

Section "Device"
        Identifier     "nvidia"
        Driver "nouveau"
        Option "Monitor-DVI-D-0" "samsung"
        Option "Monitor-VGA-1" "acer"
EndSection
Section "Monitor"
          Identifier   "samsung"
        Option "PreferredMode" "1280x1024_60.00"
EndSection
Section "Monitor"
          Identifier   "acer"
        Option "PreferredMode" "1280x1024_60.00"
          Option "RightOf" "samsung"
EndSection
Section "Screen"
    Identifier "screen1"
   Monitor "samsung"
    DefaultDepth 24
      SubSection "Display"
       Depth      24
       Virtual 2560 2048
      EndSubSection
    Device "nvidia"
EndSection
Section "ServerLayout"
    Identifier "layout1"
    Screen "screen1"
EndSection

Solution 2

I have Fedora 14 with dual monitors specified in xorg.conf, using the ATI proprietary fglrx driver, with the desktop spread across both monitors.

I believe I used aticonfig --initial=dual-head to generate my xorg.conf a year or so ago and tweaked it a bit. Try that. For reference, here is my xorg.conf.

Section "ServerLayout"
    Identifier     "aticonfig Layout"
    Screen      0  "aticonfig-Screen[0]-0" 0 0
EndSection
Section "Files"
EndSection
Section "Module"
EndSection
Section "Monitor"
    Identifier   "aticonfig-Monitor[0]-0"
    Option      "VendorName" "ATI Proprietary Driver"
    Option      "ModelName" "Generic Autodetecting Monitor"
    Option      "DPMS" "true"
EndSection
Section "Monitor"
    Identifier   "0-DFP3"
    Option      "VendorName" "ATI Proprietary Driver"
    Option      "ModelName" "Generic Autodetecting Monitor"
    Option      "DPMS" "true"
    Option      "PreferredMode" "1920x1200"
    Option      "TargetRefresh" "60"
    Option      "Position" "0 0"
    Option      "Rotate" "normal"
    Option      "Disable" "false"
EndSection
Section "Monitor"
    Identifier   "0-DFP4"
    Option      "VendorName" "ATI Proprietary Driver"
    Option      "ModelName" "Generic Autodetecting Monitor"
    Option      "DPMS" "true"
    Option      "PreferredMode" "1280x1024"
    Option      "TargetRefresh" "60"
    Option      "Position" "1920 176"
    Option      "Rotate" "normal"
    Option      "Disable" "false"
EndSection
Section "Device"
    Identifier  "aticonfig-Device[0]-0"
    Driver      "fglrx"
    Option      "Monitor-DFP3" "0-DFP3"
    Option      "Monitor-DFP4" "0-DFP4"
    BusID       "PCI:2:0:0"
EndSection
Section "Screen"
    Identifier "aticonfig-Screen[0]-0"
    Device     "aticonfig-Device[0]-0"
    Monitor    "aticonfig-Monitor[0]-0"
    DefaultDepth     24
    SubSection "Display"
        Viewport   0 0
        Virtual   3200 3200
        Depth     24
    EndSubSection
EndSection

Comments

[Thomas]

Thanks, but that didn't work for me. aticonfig generates a xorg.conf that basically displays clones of a single Desktop.