After kernel update(08-31-2022) Ubuntu 22.04 nolonger recognizes external hdmi monitor

 Output from sudo lshw

 *-display
       description: VGA compatible controller
       product: UHD Graphics 620
       vendor: Intel Corporation
       physical id: 2
       bus info: pci@0000:00:02.0
       logical name: /dev/fb0
       version: 07
       width: 64 bits
       clock: 33MHz
       capabilities: pciexpress msi pm vga_controller bus_master cap_list rom fb
       configuration: depth=32 driver=i915 latency=0 resolution=3840,2160
       resources: irq:160 memory:db000000-dbffffff memory:70000000-7fffffff ioport:f000(size=64) memory:c0000-dffff
  *-display
       description: 3D controller
       product: GP108M [GeForce MX150]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a1
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list rom
       configuration: driver=nvidia latency=0
       resources: irq:162 memory:dc000000-dcffffff memory:b0000000-bfffffff memory:c0000000-c1ffffff ioport:e000(size=128) memory:dd000000-dd07ffff

Vidoe driver currently in use:

NVIDIA server driver metapackage from NVIDIA driver 510 (proprietary)

Updated video driver to "NVISIA driver metapackaage from nvidia-driver515 (proprietary, tested)"

No difference.

"After kernel update ..."
Does it work, if you select an older version of the kernel from the grub menu?
If not, then this problem is not related to the kernel update (but perhaps to other updates)

What is the output of the command
xrandr -q

Manfred:

You didn't mention whether or not you wanted the external monitor connected when I ran xrandr, so I've done it both ways:

WITHOUT EXTERNAL MONITOR CONECTED:

Screen 0: minimum 8 x 8, current 4864 x 2160, maximum 32767 x 32767
eDP-1-1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 345mm x 194mm
   3840x2160 60.00*+ 59.98 59.97 40.00
   3200x1800 59.96 59.94
   2880x1620 59.96 59.97
   2560x1600 59.99 59.97
   2560x1440 59.99 59.99 59.96 59.95
   2048x1536 60.00
   1920x1440 60.00
   1856x1392 60.01
   1792x1344 60.01
   2048x1152 59.99 59.98 59.90 59.91
   1920x1200 59.88 59.95
   1920x1080 60.01 59.97 59.96 59.93
   1600x1200 60.00
   1680x1050 59.95 59.88
   1600x1024 60.17
   1400x1050 59.98
   1600x900 59.99 59.94 59.95 59.82
   1280x1024 60.02
   1440x900 59.89
   1400x900 59.96 59.88
   1280x960 60.00
   1440x810 60.00 59.97
   1368x768 59.88 59.85
   1360x768 59.80 59.96
   1280x800 59.99 59.97 59.81 59.91
   1152x864 60.00
   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
DP-1-1 disconnected (normal left inverted right x axis y axis)
HDMI-1-1 disconnected (normal left inverted right x axis y axis)
DP-1-2 connected 1024x768+3840+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

WITH EXTERNAL MONITOR CONNECTED:

Screen 0: minimum 8 x 8, current 4864 x 2160, maximum 32767 x 32767
eDP-1-1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 345mm x 194mm
   3840x2160 60.00*+ 59.98 59.97 40.00
   3200x1800 59.96 59.94
   2880x1620 59.96 59.97
   2560x1600 59.99 59.97
   2560x1440 59.99 59.99 59.96 59.95
   2048x1536 60.00
   1920x1440 60.00
   1856x1392 60.01
   1792x1344 60.01
   2048x1152 59.99 59.98 59.90 59.91
   1920x1200 59.88 59.95
   1920x1080 60.01 59.97 59.96 59.93
   1600x1200 60.00
   1680x1050 59.95 59.88
   1600x1024 60.17
   1400x1050 59.98
   1600x900 59.99 59.94 59.95 59.82
   1280x1024 60.02
   1440x900 59.89
   1400x900 59.96 59.88
   1280x960 60.00
   1440x810 60.00 59.97
   1368x768 59.88 59.85
   1360x768 59.80 59.96
   1280x800 59.99 59.97 59.81 59.91
   1152x864 60.00
   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
DP-1-1 disconnected (normal left inverted right x axis y axis)
HDMI-1-1 disconnected (normal left inverted right x axis y axis)
DP-1-2 connected 1024x768+3840+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

>"After kernel update ..."
>Does it work, if you select an older version of the kernel from the grub menu?
>If not, then this problem is not related to the kernel update (but perhaps to other updates)

Yes, you're correct. I should have said "after the latest Software Update." I'll try what you suggest.

If this helps at all, during the reboot, I get a long screenful of system messages. Unfortunately, they are in such a tiny font that I can't even begin to read them before they disappear.

--John

Further information:

I found that if I reboot with the external monitor connected, then plug it in *after* the system boots, the external monitor is discovered and functions normally. It's only when the monitor is connected (HDMI) at boot time that the system fails to find it.

--John

Correction. Should read:

found that if I reboot with the external monitor *dis*connected, then plug it in *after* the system boots, the external monitor is discovered and functions normally. It's only when the monitor is connected (HDMI) at boot time that the system fails to find it.

I assume that the external monitor also starts working, when you have it connected during boot, then unplug it and connect it again.

How does the xrandr output look like after plugging the monitor in only after boot?

>I assume that the external monitor also starts working, when you have it connected during boot, then unplug it and connect it again.

Not the last time I tried it. I'll try again and let you know.

>How does the xrandr output look like after plugging the monitor in only after boot?

Like this. I am currently working from the external monitor:

Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767
eDP-1-1 connected (normal left inverted right x axis y axis)
   3840x2160 60.00 + 59.98 59.97 40.00
   3200x1800 59.96 59.94
   2880x1620 59.96 59.97
   2560x1600 59.99 59.97
   2560x1440 59.99 59.99 59.96 59.95
   2048x1536 60.00
   1920x1440 60.00
   1856x1392 60.01
   1792x1344 60.01
   2048x1152 59.99 59.98 59.90 59.91
   1920x1200 59.88 59.95
   1920x1080 60.01 59.97 59.96 59.93
   1600x1200 60.00
   1680x1050 59.95 59.88
   1600x1024 60.17
   1400x1050 59.98
   1600x900 59.99 59.94 59.95 59.82
   1280x1024 60.02
   1440x900 59.89
   1400x900 59.96 59.88
   1280x960 60.00
   1440x810 60.00 59.97
   1368x768 59.88 59.85
   1360x768 59.80 59.96
   1280x800 59.99 59.97 59.81 59.91
   1152x864 60.00
   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
DP-1-1 disconnected (normal left inverted right x axis y axis)
HDMI-1-1 disconnected (normal left inverted right x axis y axis)
DP-1-2 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 477mm x 268mm
   1920x1080 60.00*+
   1680x1050 59.88
   1280x1024 75.02 60.02
   1440x900 59.90
   1280x960 60.00
   1280x800 59.91
   1152x864 75.00
   1280x720 60.00
   1024x768 75.03 70.07 60.00
   832x624 74.55
   800x600 72.19 75.00 60.32 56.25
   640x480 75.00 72.81 66.67 59.94
   720x400 70.08

Okay, I made one single change befor rebooting. I commented out the "opetions" line in the file:

/lib/modprobe.d/nvidia-kms.conf

It now looks like this:

# This file was generated by ubuntu-drivers
# Set value to 1 to enable modesetting, 0 to disable it
## Commented this option out, in effort to restore external monitor:
# options nvidia-drm modeset=1

After this, the external monitor started working again, as it was before the Software Update. I have no idea what the Update changed that makes this necessary, but as far as I can see, the system is now recognizing the second monitor normally.

Thanks for all your help.

--John