Hi,
As my native language is not English I may be missing something.
I’ll try to explain slowly
Forcing a resolution should be as close to one as you have in the options that the xrandr command does not offer
I’ll give an example of mine here:
xrandr ✔
Screen 0: minimum 320 x 200, current 1280 x 720, maximum 8192 x 8192
LVDS connected primary 1280x720+0+0 (normal left inverted right x axis y axis) 309mm x 174mm
1366x768 60.07 + 40.04
1280x720 59.97*
1152x768 59.95
1024x768 59.95
800x600 59.96
848x480 59.94
720x480 59.94
640x480 59.94
HDMI-0 connected 1280x720+0+0 (normal left inverted right x axis y axis) 697mm x 392mm
1280x720 60.00*+ 59.94
1920x1080 60.00 59.94
1920x1080i 60.00 59.94
1440x480i 59.94
720x480 60.00 59.94
720x480i 60.00 59.94
640x480 60.00 59.94
VGA-0 disconnected (normal left inverted right x axis y axis)
My monitor is at this resolution LVDS:
1366x768 60.07 + 40.04
If I want to use a lower resolution and it will work, it has to be the closest to these options:
1280x720 59.97*
1152x768 59.95
But I want it to be: 1280x800, so I have to do the following
cvt 1280 800 60
and copy everything after Modeline
Modeline "1280x800_60.00" 83.50 1280 1352 1480 1680 800 803 809 831 -hsync +vsync
Or better
"1280x800_60.00" 83.50 1280 1352 1480 1680 800 803 809 831 -hsync +vsync
From here continue to execute the hint commands.
To conclude I could not try for example the resolution 1440x480, because it wouldn’t work, it would probably give the same black screen
I hope I made you understand me and I apologize for my bad English
T+ = See you later