Someone with nvidia and external monitors via dock, found a way to make the setup usable on Ubuntu?

I’m with lenovo x1 extreme (nvidia card) that uses TB3 to connect to a dock (lenovo pro dock) and that goes to 2 external ultrawide monitors via DP.

Since updating to the 455 nvidia driver my setup is unusable.

  • if you standby it crashes

  • if you change any of the settings of the monitors, it crashes

  • if you undock it crashes.

Has anyone found a way to make it actually work?

More details:
It was working fine with 440, then popOS 20.04 (Ubuntu derrivative) auto-updated it to 455 and all those problems started happening.
I waited for popOS 20.10 with the new 5.8 kernel but unfortunately that didn’t fix anything.
And now I’m stuck with 455 because reverting drivers on popOS is non-trivial and now from my understanding 440 is not even supported by the new 5.8 kernel. So I’m stuck with working from the coach, since everything related to docking crashes…

You can try downgrading by doing these steps:

  • First check with apt-policy a previous version, since these nvidia packages upgrade to the newest even if the name says it’s an old version.
  • Try to install it with PACKAGE=VERSION, like nvidia-driver-440=440.82+really.440.64-0ubuntu6
  • It will show an error saying that can’t be installed because of mismatched versions with all packages necessary.
  • Copy the list to a text editor and get all packages with their = version
  • Install all packages with specific versions

Check a session of me doing that:

Don’t forget to check for any typos, like I did in the example.

Don’t update the system or it will install the newer version again. If that works, you’ll have to create a pin for those packages.

Try just replacing apt install … with apt-mark hold … (after you already have installed the packages), to prevent the packages from being upgraded.

I would try that but read somewhere that 440 nvidia driver is not compatible with linux kernel 5.8? Not sure if it’s true since I read it on reddit but…do you know?

I don’t know, but I find that strange. If it doesn’t work it’s easy to revert, possibly just X won’t start, so you log in on the terminal and unhold the packages, do an apt upgrade and reboot. If it doesn’t boot at all, you just select recovery mode from the grub menu, before loading linux, and then do the unhold and upgrade.