TL;DR: Connecting notebook to an external monitor with VGA doesn't work, Ubuntu recognizes an "unknown" display but nothing appears in the monitor. The monitor works on other computers.
I'm trying to use two separate monitors on my notebook, one using the HDMI output and the other the VGA output.
Currently, only the HDMI works and when I connect the VGA cable, Ubuntu recognizes a display but says it's unknown and the monitor itself doesn't detect any output. I can move the mouse to this "phantom" monitor, but the monitor doesn't show anything.
I confirmed that even if a user only the VGA output it still doesn't work and the monitor itself works using HDMI and using the VGA on another computer. It seems that the problem is the VGA connection itself.
I tried looking up for solutions, but nothing worked for me.
Does anyone here know how to solve this or what can I do to further investigate the problem?
- Ubuntu 20.04.1 LTS (Though it didn't work in the previous version as well)
- Monitor: p2319h
- Cable: VGA
- Notebook: Dell Latitude 3400 Graphic
- Card: Intel Corporation UHD Graphics 620 (Whiskey Lake) (rev 02)
xrandr output:
Screen 0: minimum 320 x 200, current 4950 x 1080, maximum 16384 x 16384
eDP-1 connected primary 1366x768+0+312 (normal left inverted right x axis y axis) 309mm x 174mm 1366x768 60.06*+ 48.05 1360x768 59.80 59.96 1280x720 60.00 59.99 59.86 59.74 1024x768 60.04 60.00 960x720 60.00 928x696 60.05 896x672 60.01 1024x576 59.95 59.96 59.90 59.82 960x600 59.93 60.00 960x540 59.96 59.99 59.63 59.82 800x600 60.00 60.32 56.25 840x525 60.01 59.88 864x486 59.92 59.57 800x512 60.17 700x525 59.98 800x450 59.95 59.82 640x512 60.02 720x450 59.89 700x450 59.96 59.88 640x480 60.00 59.94 720x405 59.51 58.99 684x384 59.88 59.85 680x384 59.80 59.96 640x400 59.88 59.98 576x432 60.06 640x360 59.86 59.83 59.84 59.32 512x384 60.00 512x288 60.00 59.92 480x270 59.63 59.82 400x300 60.32 56.34 432x243 59.92 59.57 320x240 60.05 360x202 59.51 59.13 320x180 59.84 59.32
HDMI-1 connected 2560x1080+1366+0 (normal left inverted right x axis y axis) 673mm x 284mm 2560x1080 60.00*+ 1920x1080 60.00 50.00 59.94 1920x1080i 60.00 50.00 59.94 1680x1050 59.88 1600x900 60.00 1280x1024 75.02 60.02 1152x864 75.00 1280x720 60.00 50.00 59.94 1024x768 75.03 60.00 800x600 75.00 60.32 720x576 50.00 720x480 60.00 59.94 640x480 75.00 60.00 59.94 720x400 70.08
DP-1 connected 1024x768+3926+0 (normal left inverted right x axis y axis) 0mm x 0mm 1024x768 60.00* 800x600 60.32 56.25 848x480 60.00 640x480 59.94
HDMI-2 disconnected (normal left inverted right x axis y axis)1 Answer
I had the same issue and it was resolved by:
sudo ubuntu-drivers autoinstall 
