What to do re "Failed to start Simple Desktop Display Manager" in ver 6 and other errors

[pwrcul]

I now have failure to start the display manager on top of other KDE 6 errors and am unsure of a path forward (or backward as I had been running Back In Time and another snapshot program).

KDE 6 happened with an update by Discover and I had problems with the main panel. Then as I tried to keep on working while looking into the panel issues my system crashed.
Upon restarting, I got both Nvidia and CPU errors and failure ( Failed to start Simple Desktop Display Manager) messages:


[

0.004211] common_interrupt: 10.55 No irq handler for vector

2.992725] nvidia-gpu 0000:09:00.3: i2c timeout error e0000000

2.992783] ucsi_ccg 0-0008: 12c_transfer failed -110 2.992830] ucsi_ccg 0-0008: ucsi_ccg_init failed - -110

[ 6.622015]

[

6.628139] kvm_amd: SVM disabled (by BIOS) in MSR_VM_CR on CPU 29

[ 7.072159] usb 7-4: 4:1: cannot get freq at ep 0x84 [FAILED] Failed to start Simple Desktop Display Manager.

At first I thought I had a CPU failure, but it appears that it is a software problem. I am baffled. I am unclear how much KDE 6 issues are the source of the problem.

If you have suggestions I would like to know what you recommend.

[pwrcul]

I burned a USB stick with Neon ISO for 12 April 24.
I booted a Live Neon so I don't think I have a CPU hardware issue!

[pwrcul]

I assumed I also had a problem with an incomplete KDE versionr 6 update.
When my box booted I had the same boot problem of a Failure "to start Simple Desktop Display Manager."
I did Ctrl Alt F3 and then logged in and issued sudo apt update and sudo apt full-upgrade.
With that I got back a bootable systen--but with the incomplete main panel.

I backed up with Timeshift and Back in time,

Now I will try to understand the new panels and get a working system.

I am pleased my situation is much better than I feared.
My thanks to forum participants who wrote up their accounts of problems with KDE 6 Neon and their soliutions'

[pwrcul]

I would call this a partial resolution. I still have problems with the new panels.

[Schwarzer Kater]

Slightly OT: Unfortunately the new Plasma Panels in Plasma 6 are still quite buggy…

[pwrcul]

If you or anyone has recommendations for setting up the display configuration for two monitors and using the panels well I would welcome good sources. I would like to use System Settings, etc.

Most likely I will need some fixes.

I have two monitors but they show the same content with two cursors and no panel.....