Black screen after logout

[lydloke]

I installed Kubuntu 24.04 and it works well, apart from when I log out the screen is black, and I have to do a hard restart. When I reboot the login screen is normal. I did remove Snap though after installation: can it be related to that?

[Snowhog]

Welcome to KFN.

When you logout, how long are you waiting before going for a hard restart? Logging out isn't instantaneous; there are background services that are doing cleanup, and in some cases, that can take a bit of time.

[lydloke]

I waited a few minutes, but the screen stays black. The GPU is NVIDIA GA104 (GeForce RTX 3069) and the driver configuration is X.Org X Server.

[Schwarzer Kater]

[…] I did remove Snap though after installation: can it be related to that?

Normally: it can not. This depends what you exactly did to "remove Snap", of course. And if you e.g. accidentally removed something else.

It is much more likely that your problem is connected to the Nvidia GPU and drivers…
Did you install the proprietary Nvidia drivers? If yes: which version and from where?

[lydloke]

I initially used the default X.Org X Server. Then I tried nvidia driver 535-open (proprietary), which resulted in a black screen when logged in. I did not manage to fix it in safe mode, so I had to reinstall Kubuntu. I usually do not log out, so I will keep it like that until a fix comes along.

[Schwarzer Kater]

If you have a Nvidia GPU and have to use the proprietary drivers: dont use the nvidia-driver-xxx-open one - the -open one has always caused trouble AFAIK…

You could also try the nvidia-driver-550 for your GeForce RTX 3060 if the nvidia-driver-535 does not work properly (it seems to have been released to the repositories for Kubuntu 24.04 LTS recently).

[lydloke]

If the the -open drivers always cause trouble then they probably shouldn't be drivers list.

[Schwarzer Kater]

You would have to tell this to Canonical/Ubuntu…
And for some people it may work (perhaps better than the non -open one). For the majority it clearly doesn't.

With Nvidia GPUs and Linux many people will run into trouble sooner or later anyhow.

Did you find a solution yet?

[lydloke]

I have decided to continue with the default X.Org X Server for the time being. I works well as long as I do not log out, and I almost never do, as my computer goes into power saving mode when I don't use it.

[spikederailed]

Like lydloke I am unable to log out. Screen goes black and never returns to SDDM. I only noticed as I was trying to logout to test switching sessions between X and Wayland. Issue seems to exist across Nvidia 535 proprietary drivers from canonical, nvidia 550 from the PPA, and Nouveau. Ive given it almost 10 minutes and got nothing. I havent done much troubleshooting past that, just caulking another one up for the issue I noticed while trying to get Wayland to work after upgrading from 23.10

[spikederailed]

SO i decided to spend a few minutes poking around and see if I could figured out why it just went black screen forever.

Settings -> Startup and Shutdown -> Workspace - Desktop Session.

Change under "Session Restore" from On login, launch apps that were open: selected "Start with an empty session" instead of "on last logout". and was for the first time able to log out and get back to SDDM to be able to log back in.

[Schwarzer Kater]

Good catch. Your solution might work for someone else, too.
"Session restore" can be responsible for strange effects - in any operating system.

And welcome.

[spikederailed]

Under setting Login Screen(SDDM) i have two instances of Breeze listed, which is odd. I just tested again by setting back to "on last logout", this time i could logout, but it threw an error that it failed to start plasma trying to login. Ive been able to log in and out multiple times with success if i leave the setting on "Start with an empty session"

I have to guess at this time something about the way theyre trying to cache the Plasma 5 session on a logout is just very buggy.

[lydloke]

It didn't work for me.

[Escovan]

SO i decided to spend a few minutes poking around and see if I could figured out why it just went black screen forever.

Settings -> Startup and Shutdown -> Workspace - Desktop Session.

Change under "Session Restore" from On login, launch apps that were open: selected "Start with an empty session" instead of "on last logout". and was for the first time able to log out and get back to SDDM to be able to log back in.

This I'm going to try next.
I've installed Kubuntu several times, but I have issues after the first reboot, to enter the desktop.