Ubuntu 18 2nd monitor detected but no signal with vga-to-dvi adapter and AMD graphics card
By John Campbell •
My setup:
- Ubuntu 18.04.1 LTS (just upgraded, I had no problem on 16)
- VGA to DVI converter (So my 2nd monitor has vga port)
- AMD Radeon R9 285 with what I believe are the latest AMDGPU drivers
- Dell 20"IN2010N LCD monitor
I've tried rebooting several times and changing resolution, disabling and re-enabling the monitor from both xrandr and settings, and I still get the same problem.
The second monitor works fine on booting until it gets to the grub menu, the it gets no signal. If I boot to windows it works fine.
xrandr output is as follows:
Screen 0: minimum 320 x 200, current 3520 x 1080, maximum 16384 x 16384
DisplayPort-0 disconnected (normal left inverted right x axis y axis)
HDMI-A-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 509mm x 286mm 1920x1080 60.00*+ 50.00 59.94 1600x1200 60.00 1680x1050 59.88 1280x1024 60.02 1440x900 59.90 1280x960 60.00 1280x800 60.00 1280x720 60.00 50.00 59.94 1024x768 60.00 800x600 60.32 720x576 50.00 720x480 60.00 59.94 640x480 60.00 59.94 720x400 70.08
DVI-D-0 disconnected (normal left inverted right x axis y axis)
DVI-D-1 connected 1600x900+1920+0 (normal left inverted right x axis y axis) 443mm x 249mm 1600x900 59.98*+ 1280x1024 75.02 60.02 1440x900 59.98 1280x800 59.98 1152x864 75.00 1280x720 59.98 1024x768 75.03 60.00 800x600 75.00 60.32 640x480 75.00 59.94 720x400 70.08So it's detecting the monitor as a DVI-D-1 connection. I'm not sure why it's DVI-D here, because it's plugged into a DVI-I port.
1 Answer
I fixed this by reverting to the previous kernel version (4.15.0-36 -> 4.4.0-93) as per these instructions. I'm still not sure exactly what the problem was, but now my second monitor is being picked up as DVI-I so I guess the kernel update made it misidentify that connection as DVI-D?
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