I am running out of ideas to try. When I boot my 22.04 Desktop on bare metal, everything looks normal until the end of the boot process, where I would expect to see my GUI login, all I get is a black screen. I can ssh into the machine fine. This machine is running as a KVM host. All the VMs are running ubuntu server 22.04 and are all running fine.
In full disclosure. About 2 years ago when I set this machine up, I had purged the gnome full desktop and installed Vanilla gnome desktop. It has run fine all along, I think until a recent update. So, I reversed that and purged the Vanilla desktop and installed the gnome full desktop again. Still no GUI after boot/reboot.
The key issue here is that your system has an AMD iGPU, but X.org reports the NVIDIA driver being loaded. That mismatch commonly causes a black screen.
I’d recommend purging any leftover NVIDIA packages:
Thank you both for you suggestions. Here is what I did. @tea-for-one I did all your suggestions except the grub edit. Rebooted each time and no change. Then I went on and performed the suggestions by @MesterPerfect and rebooted each time and no change. Then I last did the grub edit suggested by @tea-for-one and this does give a low resolution (big print) login screen. However prior to getting the login screen, I see these lines post at the top of the screen:
1.570762] mpt2sas_cm0: overriding NVDATA EEDPTagMode setting
11.297642] [drm:amdgpu_init [amdgpu]] *ERROR* VGACON disables amdgpu kernel modesetting.
16.6140781 [drm:amdgpu_init [amdgpu]] *ERROR* VGACON disables amdgpu kernel modesetting.
19.647109] libvirt-guests.sh[4695]: libvirt-guests is configured not to start any guests on boot
Not sure if this output gives any further housekeeping to do.
You received some good advice above. Sometimes on has to try several things to sort out what the best solution is.
A couple of things here.
The error above is triggered by nomodset with some AMD products. Basically, nomodset keeps the amdgpu kernel module from loading. That explains that part, which you can fix by removing the nomodset. Problem is that you’ll be back to blank screen.
We need to solve a deeper problem before removing the nomodset parameter. So far, what I’ve found in research is that the kernel parameter
amdgpu.dc=1
can precipitate the behavior you have noted in some hardware configurations, Cezanne seeming to be a frequent culprit.
That parameter controls AMD’s display core. The default was 0 until some later kernel versions started using 1 as the default.
The solution, if that is the cause, is to (temporarily for testing) set the kernel parameter to
amdgpu.dc=0
and remove nomodset.
This gives a pretty good rundown on temporarily setting a kernel parameter (so you can test), and then making the change permanent if it solves your issue.
Thanks @qiii I tested this and it gave screen artifacts during the bootsplash and eventually the screen froze.
The VMs are not in need of a GPU.
Originally, hareware-wise, this machine used to have an Nvidia GT-1030 card in it along with an AMD 5600X CPU. About a year later, I replaced the CPU with an AMD 5700G with onboard video, and I removed & uninstalled the Nvidia card. It all has worked since then for about 1.5 years. Perhaps I am getting close to needing a reinstall.
This install is a root on ZFS with daily snapshots. If I am close to a reinstall, I may try a rollback to about 1 month ago and see if that recovers the display. If not, no biggie, I have good backups.