Yesterday, I installed all the latest Ubuntu updates on my System 76 laptop with intel graphics, and I think one of them has caused my problem. I have tried the steps here: HDMI stops working when DisplayPort is unplugged

and they fail:

$ sudo lshw -C video *-display description: VGA compatible controller product: Intel Corporation vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 07 width: 64 bits clock: 33MHz capabilities: pciexpress msi pm vga_controller bus_master cap_list rom configuration: driver=i915 latency=0 resources: irq:135 memory:db000000-dbffffff memory:90000000-9fffffff ioport:f000(size=64) memory:c0000-dffff
$ xrandr
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 293mm x 165mm 3200x1800 59.70 + 2048x1536 60.00 1920x1440 60.00 1856x1392 60.01 1792x1344 60.01 1920x1200 59.95 1920x1080 59.93* 1600x1200 60.00 1680x1050 59.95 59.88 1600x1024 60.17 1400x1050 59.98 1280x1024 60.02 1440x900 59.89 1280x960 60.00 1360x768 59.80 59.96 1152x864 60.00 1024x768 60.04 60.00 960x720 60.00 928x696 60.05 896x672 60.01 960x600 60.00 960x540 59.99 800x600 60.00 60.32 56.25 840x525 60.01 59.88 800x512 60.17 700x525 59.98 640x512 60.02 720x450 59.89 640x480 60.00 59.94 680x384 59.80 59.96 576x432 60.06 512x384 60.00 400x300 60.32 56.34 320x240 60.05
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
$
$ xrandr --addmode HDMI-1 1920x1080
$ xrandr --output eDP-1 --mode 1920x1080 --output HDMI-1 --mode 1920x1080 --same-as eDP-1
xrandr: Configure crtc 1 failed
$ 

I have power cycled the laptop and the monitor, still no luck. I updated the intel-video drivers:

 intel-graphics-update-tool

I think this is related to the intel-microcode update I did yesterday but I am not sure how to back it out (or if I should).

2

1 Answer

Annoyingly, I stumbled to the solution while trying to fix the problem. I run gnome3 on this machine, and in and attempt to fix the problem with this:

sudo apt-get install xserver-xorg-video-intel xorg-video-abi-20 xserver-xorg-core

and it removed ubuntu-gnome-desktop and many xorg drivers... so when I rebooted, the keyboard and mouse did not work. I booted into a live CD, mounted and chroot to the main partition and removed xserver-xorg-video-intel and reinstalled ubuntu-gnome-desktop and all the xorg drivers came along with it.

When I rebooted, back to the main partition, I had return functionality to the keyboard and mouse and the external monitor worked too.