I am confronted with a problem when connecting the external monitor while the computer is open.
At that point it seems that xrandr adopts one of the combinations that do not work.
As a workaround to the other larger problem, I want to be able to modify the default display settings that xrandr has upon connecting the external monitor while the computer is running. (So that I may put a setting that avoids the problem: either by a combination of resolutions that works, or by starting just one of the monitors).
If I connect the external monitor before starting the system, xrandr selects mirror display at a certain rather low resolution that works.
xrandr Screen 0: minimum 320 x 200, current 1360 x 768, maximum 4096 x 4096 VGA-0 connected 1360x768+0+0 (normal left inverted right x axis y axis) 580mm x 320mm 1360x768 60.0*+ 1280x720 60.0 1024x768 60.0 800x600 60.3 640x480 60.0 DVI-0 disconnected (normal left inverted right x axis y axis) LVDS connected (normal left inverted right x axis y axis) 1680x1050 60.1 + 1400x1050 60.0 1280x1024 59.9 1440x900 59.9 1280x960 59.9 1280x854 59.9 1280x800 59.8 1280x720 59.9 1152x768 59.8 1024x768 59.9 800x600 59.9 848x480 59.7 720x480 59.7 640x480 59.4 S-video disconnected (normal left inverted right x axis y axis)
When I connect the external desktop I want to use it at its best resolution (which, considering my other problem, excludes the use of the internal monitor). I can set from GUI the resolution for dual monitor. But upon connecting the cable for the external monitor, I want the internal to go off and the external to have 1360x768 - just like they were when I ran the
xrandr command above.