I am confronted with a problem of conflict of resolutions (this is a separate question), which makes the display image distorted on both monitors.
But this bothers me the most 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.