Dual Monitors: Dual-Link DVI + HDMI

Finally, this Just Worked…

The problem was to get both a landscape and a portrait monitor working. The complexity came from the landscape monitor, a 2560×1440 Dell U2711, which requires either a Dual-Link DVI or HDMI input to reach full resolution. The portrait monitor, an old 1608×1050 Dell 2005FPW, uses Single-Link DVI.

The previous attempt with an nVidia GT430 card failed: both DVI outputs were Single-Link, despite their connector’s appearance. It had worked OK with the previous landscape monitor, a 1600×1200 Dell 2001FP.

So I picked up a low-end nVidia GT610 card that advertised both Dual-Link DVI and HDMI. I plugged the DVI cable into the U2711 and it lit up at full resolution, then I plugged the HDMI into the 2005FPW and it lit right up. By some miracle that didn’t involve tweaking an xorg.conf file, the 2005FPW immediately displayed the pixels lying to the right of the U2711, exactly as I wanted; all I had to do was rotate the image using xrandr.

Not only that, but the version of xsetwacom in Xubuntu 12.10 once again respects the MapToOutput "HEAD-0" option that restricts the stylus to the U2711 monitor. That means I can’t put the GIMP toolbars and suchlike on the portrait monitor, but the U2711 has enough dots to render that moot.

Although the Dell doc strongly suggests that the on-board VGA and Displayport outputs don’t work with a PCI-E video card plugged in, xrandr reports:

Screen 0: minimum 8 x 8, current 3610 x 1680, maximum 16384 x 16384
DVI-I-0 disconnected (normal left inverted right x axis y axis)
VGA-0 disconnected (normal left inverted right x axis y axis)
DVI-I-1 connected 2560x1440+0+0 (normal left inverted right x axis y axis) 597mm x 336mm
   2560x1440      60.0*+
   1920x1200      59.9
   1680x1050      60.0
   1600x1200      60.0
   1280x1024      75.0     60.0
   1280x800       59.8
   1152x864       75.0
   1024x768       75.0     60.0
   800x600        75.0     60.3
   640x480        75.0     59.9
HDMI-0 connected 1050x1680+2560+0 left (normal left inverted right x axis y axis) 434mm x 270mm
   1680x1050      59.9*+
   1280x1024      75.0     60.0
   1152x864       75.0
   1024x768       75.0     60.0
   800x600        75.0     60.3
   640x480        75.0     59.9

I’m not going to connect the DVI-I-0 and VGA-0 outputs; my physical desk has no room for more pixels…

The ~/.xprofile file now looks like:

setxkbmap -option terminate:ctrl_alt_bksp
xrandr --output HDMI-0 --rotate left
xrandr --dpi 100x100
xsetwacom --verbose set "Wacom Graphire3 6x8 stylus" MapToOutput "HEAD-0"
xsetwacom --verbose set "Wacom Graphire3 6x8 eraser" MapToOutput "HEAD-0"

Phew…