I have a display that is connected to my GeForce RTX 2070 using USB-C-0 on a Ubuntu 20.10. This display device can show images at 60 Hz with 1920x1080 resolution. However, for some reason, the display resolution is set to 1740x980, and xrandr shows this as the only mode offered:
USB-C-0 connected 1740x980+2100+1080 (normal left inverted right x axis y axis) 1920mm x 1080mm
1740x980 60.00*+
Besides, the display current shows a band of red, green and blue stripes overlayed on top of the displayed images. I contacted the display manufacturer and they claim that this is all about wrong EDID settings, they even offered values such as pixel clock.
The trouble is xrandr do not work with nvidia driver properly. I can not add new modes or force the display to be at some pixel clock or resolution. I have visited nvidia-settings, however, all that offers is writing the existing EDID settings of a display to a bin or txt file.
So my question how does one add a new mode for any display while NVIDIA driver does not allow it?
kaan:~$ xrandr --newmode "1920x1080R" 136.00 1920 1980 2000 2060 1080 1088 1092 1100 +hsync -vsync
kaan:~$ xrandr --addmode USB-C-0 "1920X1080R"
xrandr: cannot find mode "1920X1080R"
kaan:~$ xrandr --output USB-C-0 1920x1080R
xrandr: unrecognized option '1920x1080R'
Try 'xrandr --help' for more information.
kaan:~$ xrandr
....
USB-C-0 connected 1740x980+2100+1080 (normal left inverted right x axis y axis) 1920mm x 1080mm
1740x980 60.00*+
1920x1080R (0x27c) 136.000MHz +HSync -VSync
h: width 1920 start 1980 end 2000 total 2060 skew 0 clock 66.02KHz
v: height 1080 start 1088 end 1092 total 1100 clock 60.02Hz