Desktop bricked/glitched on fresh install?

[Wobbelblob]

Hey, so I wanted to try Kubuntu, but I ran into the following problem: Already on starting from my USB stick, I was greeted with the fact that on the mainscreen, only the bottom 10% where shown. That was fixed after I got into the safe boot option to install it, which was fine. But after installing and booting it, same thing happens. From the main screen, only the bottom ~10% with the task bar are visible. The mouse is not visible if I got into the black area, but everything apparently works. Second screen is fine. Considering that the safe boot fixed it during installing, I assume it is a problem with my Nvidia-card? Any advises on how to fix that?

Kubuntu version: Kubuntu 25.10 Plasma 6, current download from Kubuntu.org
Graphics: Nvidia 2080TI
Other OS? Yes, I have an installation of Bazzite OS, Zorin OS and Windows. Zorin mostly because I am too lazy to delete it.

Anything else needed?

[die.boer]

Hey, so I wanted to try Kubuntu, but I ran into the following problem: Already on starting from my USB stick, I was greeted with the fact that on the mainscreen, only the bottom 10% where shown. That was fixed after I got into the safe boot option to install it, which was fine. But after installing and booting it, same thing happens. From the main screen, only the bottom ~10% with the task bar are visible. The mouse is not visible if I got into the black area, but everything apparently works. Second screen is fine. Considering that the safe boot fixed it during installing, I assume it is a problem with my Nvidia-card? Any advises on how to fix that?

Kubuntu version: Kubuntu 25.10 Plasma 6, current download from Kubuntu.org
Graphics: Nvidia 2080TI
Other OS? Yes, I have an installation of Bazzite OS, Zorin OS and Windows. Zorin mostly because I am too lazy to delete it.

Anything else needed?

at the grub menu choose advanced options and boot into recovery mode , once inside run

sudo ubuntu-drivers autoinstall 

and reboot

[Wobbelblob]

That command always threw an error about the command not existing. But when I add an "install" between drivers and autoinstall, I get the info that all drivers are installed. Desktop is still broken though. Sidenote: I don't get the option to boot to Kubuntu from the GRUB menu, I always need to go into BIOS to directly boot that drive, which prompts a slightly differently looking GRUB menu, which replaces the Bazzite boot option with Kubuntu. Do both OS conflict with each other, even though they are installed on different drives?

[oshunluvr]

That command always threw an error about the command not existing. But when I add an "install" between drivers and autoinstall, I get the info that all drivers are installed. Desktop is still broken though. Sidenote: I don't get the option to boot to Kubuntu from the GRUB menu, I always need to go into BIOS to directly boot that drive, which prompts a slightly differently looking GRUB menu, which replaces the Bazzite boot option with Kubuntu. Do both OS conflict with each other, even though they are installed on different drives?

If you install GRUB (or whatever boot loader) on different drives, then you should be good. Sounds like you might need to update the both GRUB installs. If you enable OS-PROBER on Kubuntu, it should find Bazzite and let you boot to Bazzite from the Kubuntu GRUB.

IDK anything about Bazzite or what it uses to boot. It's also possible it's an EFI related error, which I'm not very familiar with.

[Wobbelblob]

Okay, I admit, you lost me here. I think I installed GRUB on different drives? All my OS are installed on different drives, so GRUB should be as well?

[die.boer]

please post output of these 2 commands:

lsmod | grep nvidia

nvidia-smi

also have you tried X11 rather than Wayland ?