Comment 2 for bug 572196

Just to update the the behaviour somewhat:

According to xrandr, the LVDS (LCD panel) screen is connected. I can use xrandr to tell the LVDS screen what resolution to display, and can set the display to off. When the display is set to off, the backlight goes off, suggesting that the panel is simply not being sent the signal when it is on.

However, LVDS still describes the panel incorrectly - it should be 1920x 1200, but I get the following from xrandr...

roger@ubuntu:~$ xrandr --prop
Screen 0: minimum 320 x 200, current 1400 x 1050, maximum 1600 x 1600
LVDS connected 1400x1050+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
 BACKLIGHT: 7 (0x00000007) range: (0,7)
 SignalFormat: DisplayPort
 ConnectorType: Panel
   1400x1050 60.2*+
   1280x1024 60.2 +
   1280x960 60.2 +
   1280x800 60.2 +
   1152x864 60.2 +
   1280x768 60.2 +
   1280x720 60.2 +
   1024x768 60.2 +
   1024x600 60.2 +
   800x600 60.2 +
   800x480 60.2 +
   720x480 60.2 +
   640x480 60.2 +
DFP1 disconnected (normal left inverted right x axis y axis)
 SignalFormat: TMDS
 ConnectorType: HDMI
CRT1 connected 1400x1050+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
 SignalFormat: VGA
 ConnectorType: VGA
   1600x1200 60.0 +
   1400x1050 60.0*
   1280x1024 75.0 60.0
   1440x900 59.9
   1280x960 60.0
   1280x800 75.0 60.0
   1152x864 75.0 60.0
   1280x768 59.9
   1280x720 60.0
   1024x768 75.0 60.0
   1024x600 60.0
   800x600 75.0 60.3
   800x480 60.0
   720x480 60.0
   640x480 75.0 60.0

Roger Barrett.