Second monitor isn’t recognised anymore after updates and restart (Ubuntu Pro 24.04.2 LTS)

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Hi everyone,
yesterday I installed some suggested updates and then just left my PC in standby overnight. When I restarted it today, my second monitor was no longer being detected. Both monitors are connected via DisplayPort to one of the two Quadro M2000 cards.

What are my machine’s specifications?

Type: DesktopPC
Name: Fujitsu Celsius M740 Power
Monitor: 2x LG 24BN550
CPU: E5-1650 v4 3,6 GHz
RAM Memory: 32 GB
GPU: 2x NVIDIA Quadro M2000
Ubuntu (Pro) 24.04.02 LTS

What steps have I taken:

I’ve already tried the most common fixes.

  1. (as recommended here: https://askubuntu.com/questions/140663/ubuntu-not-detecting-second-monitor
Unplug the display (HDMI cable) from the machine.
Reboot the machine.
Plug-in the second display.
  1. I also tried purging the NVIDIA driver and reinstalling it via autoinstall.
sudo apt-get remove --purge nvidia-*
sudo ubuntu-drivers devices
sudo ubuntu-drivers autoinstall

None of that has helped so far.
Using less /var/log/apt/history.log I checked what was changed during the update, which made me suspect the NVIDIA drivers.

Here’s an excerpt from the log that I believe contains the relevant parts:

Start-Date: 2025-08-30  14:56:43
Commandline: /usr/bin/unattended-upgrade
Upgrade: sudo:amd64 (1.9.15p5-3ubuntu5, 1.9.15p5-3ubuntu5.24.04.1)
End-Date: 2025-08-30  14:56:49

Start-Date: 2025-08-30  14:56:51
Commandline: /usr/bin/unattended-upgrade
Upgrade: libdjvulibre-text:amd64 (3.5.28-2build4, 3.5.28-2ubuntu0.24.04.1), libdjvulibre21:amd64 (3.5.28-2build4, 3.5.28-2ubuntu0.24.04.1)
End-Date: 2025-08-30  14:56:55

Start-Date: 2025-08-30  14:56:58
Commandline: /usr/bin/unattended-upgrade
Upgrade: cloud-init:amd64 (25.1.2-0ubuntu0~24.04.1, 25.1.4-0ubuntu0~24.04.1)
End-Date: 2025-08-30  14:57:05

Start-Date: 2025-08-30  14:57:07
Commandline: /usr/bin/unattended-upgrade
Remove: linux-tools-6.8.0-49:amd64 (6.8.0-49.49), linux-tools-6.8.0-49-generic:amd64 (6.8.0-49.49)
End-Date: 2025-08-30  14:57:08

Start-Date: 2025-08-30  14:57:10
Commandline: /usr/bin/unattended-upgrade
Remove: linux-signatures-nvidia-6.8.0-49-generic:amd64 (6.8.0-49.49+1), linux-modules-nvidia-550-6.8.0-49-generic:amd64 (6.8.0-49.49+1)
End-Date: 2025-08-30  14:57:17

Start-Date: 2025-08-30  14:57:20
Commandline: /usr/bin/unattended-upgrade
Remove: linux-image-6.8.0-49-generic:amd64 (6.8.0-49.49)
End-Date: 2025-08-30  14:57:22

Start-Date: 2025-08-30  14:57:25
Commandline: /usr/bin/unattended-upgrade
Remove: linux-modules-6.8.0-49-generic:amd64 (6.8.0-49.49), linux-modules-extra-6.8.0-49-generic:amd64 (6.8.0-49.49)
End-Date: 2025-08-30  14:57:26

Any suggestions on what else I could specifically try would be greatly appreciated.

2

If someone else has the same problem, this solution worked for me. I just forgot to properly restart the system.

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