There's a lot of evidence that more than one monitor improves productivity. I am firmly convinced by this (and am not at all influenced by the fact that having two monitors is cool). I recently binned a 19-inch CRT (much-loved but sadly blurring) and replaced it with a LG 21.5-inch LCD 1902x1080 screen. This was cabled up to the VGA port, as I use a KVM box to use the same monitor/keyboard/mouse combination on my servers. Very nice; maybe two would be even nicer.
After a few weeks I bought the same LG screen, but with added digital TV tuner (an additonal £20; I'm not sure I understand the economics). This connected to the DVI port on the ATI Radeon 4670HD graphics card on amber and gave an even better quality display.
Getting this setup working on Windows 7 was easy. A little more difficult on Debian squeeze...
The proprietry drivers (fglrx) from ATI favour an Xinerama setup,
although this is now deprecated in favour of xrandr. So,
my challenge was to move from the Xinerama, ATI-generated
/etc/X11/xorg.conf file to something that would be supported by
xrandr.
I figured I would get X to generate to
new /etc/X11/xorg.conf file, using
X -configure
This did not work, as the fglrx driver died in the middle of the X
probe process, as shown by this snippet from the X11.xorg.log
(WW) Falling back to old probe method for fglrx (II) Loading PCS database from /etc/ati/amdpcsdb (WW) fglrx: No matching Device section for instance (BusID PCI:0@1:0:1) found (**) ChipID override: 0x9490 (**) Chipset Supported AMD Graphics Processor (0x9490) found Backtrace: 0: X (xorg_backtrace+0x3b) [0x80adedb] 1: X (0x8048000+0x5aab5) [0x80a2ab5] 2: (vdso) (__kernel_rt_sigreturn+0x0) [0xb788340c] 3: /usr/lib/xorg/modules/drivers/fglrx_drv.so (atiddxProbe+0x29) [0xb6a0a789] 4: X (xf86CallDriverProbe+0x182) [0x80b00e2] 5: X (DoConfigure+0x1b5) [0x80c0a85] 6: X (InitOutput+0x1da) [0x80b05ca] 7: X (0x8048000+0x1e7f0) [0x80667f0] 8: /lib/i686/cmov/libc.so.6 (__libc_start_main+0xe6) [0xb75b9c76] 9: X (0x8048000+0x1e5a1) [0x80665a1] Segmentation fault at address (nil) Fatal server error: Caught signal 11 (Segmentation fault). Server aborting
To work around this, I de-installed the fglrx driver (using
/usr/share/ati/fglrx-uninstall.sh) and re-ran the X
-configure process. This did generate a new xorg.conf
file, defaulting to the radeonhd driver. Sadly, this
driver seemed unable to support the full resolution offered by the
monitor when connected to the VGA port, so I re-installed the
fglrx driver and manually edited
the /etc/X11/xorg.conf file to use fglrx.
Finally, to get xrandr to work, I had to add these two
lines to the Display subsection in the Screen
section of the /etc/X11/xorg.conf file, shown below:
Modes "1920x1080" Virtual 3840 3840
The complete xorg.conf file is shown below:
Section "ServerLayout" Identifier "X.org Configured" Screen 0 "Screen0" 0 0 InputDevice "Mouse0" "CorePointer" InputDevice "Keyboard0" "CoreKeyboard" EndSection Section "Files" ModulePath "/usr/lib/xorg/modules" FontPath "/usr/share/fonts/X11/misc" FontPath "/usr/share/fonts/X11/100dpi/:unscaled" FontPath "/usr/share/fonts/X11/75dpi/:unscaled" FontPath "/usr/share/fonts/X11/Type1" FontPath "/usr/share/fonts/X11/100dpi" FontPath "/usr/share/fonts/X11/75dpi" FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType" FontPath "built-ins" EndSection Section "Module" Load "dbe" Load "glx" Load "extmod" Load "dri2" Load "FGL.renamed.libdri" Load "record" EndSection Section "InputDevice" Identifier "Keyboard0" Driver "kbd" EndSection Section "InputDevice" Identifier "Mouse0" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/input/mice" Option "ZAxisMapping" "4 5 6 7" EndSection Section "Monitor" Identifier "Monitor0" VendorName "Monitor Vendor" ModelName "Monitor Model" EndSection Section "Device" Identifier "Card0" Driver "fglrx" VendorName "ATI Technologies Inc" BoardName "RV730XT [Radeon HD 4670]" BusID "PCI:1:0:0" EndSection Section "Screen" Identifier "Screen0" Device "Card0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Modes "1920x1080" Virtual 3840 3840 Depth 24 EndSubSection EndSection
You will note that the Virtual direction states 3840x3840.
I originally specified 3840x1080, but xrandr was not happy
as it said, on attempting to use both monitors, that the physical
pixel dimensions exceeded the Virtual specification.
The command to render onto two monitors is:
xrandr --output CRT2 --auto --left-of DFP1
which I placed just before the window manager invocation in my
~/.xinitrc file.
To determine which display devices are visible to xrandr,
you can issue the xrandr -q command. Example output is
shown below:
[mark@amber:~] xrandr -q Screen 0: minimum 320 x 200, current 3840 x 1080, maximum 3840 x 3840 DFP1 connected 1920x1080+1920+0 (normal left inverted right x axis y axis) 598mm x 336mm 1920x1080 59.9*+ 1776x1000 60.0 + 1280x720 60.0 + 1680x1050 60.0 1400x1050 60.0 1280x1024 75.0 60.0 1440x900 59.9 1280x960 75.0 60.0 1280x800 75.0 60.0 1152x864 75.0 60.0 1280x768 74.9 59.9 1024x768 75.0 70.1 60.0 1152x648 60.0 800x600 75.0 70.0 60.3 720x480 60.0 640x480 75.0 60.0 DFP2 disconnected (normal left inverted right x axis y axis) CRT1 disconnected (normal left inverted right x axis y axis) CRT2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 477mm x 268mm 1920x1080 60.0*+ 1680x1050 60.0 1400x1050 60.0 1280x1024 75.0 60.0 1440x900 59.9 1280x960 75.0 60.0 1280x800 75.0 60.0 1152x864 75.0 60.0 1280x768 74.9 59.9 1280x720 60.0 1024x768 75.0 60.0 800x600 75.0 60.3 56.2 720x480 60.0 640x480 75.0 60.0
