Today I saw a ray of hope.
New Nvidia driver 610.43.02.
So, I unlocked kernel, update to 7.0.9, install 610.43.02 and rebooted.
SDDM appears (great!) but incredibly slowly. So, if SDDM goes slowly, KDE Plasma will go worst.
Instead to enter KDE Plasma, I rebooted and add to the parameters kernel in Grub initcall_blacklist=sysfb_init. SDDM appears fast (and I have TTY and the boot messages available) but when I enter in KDE Plasma, Kwin crashed.
I started a game in Steam and Kwin crashed again.
Note: Seems that the 610.43.02 have problems with some Wayland compositors and seems that KDE Plasma 6.7 will fix this. Devs are working to fix 6.6:
So… “I’ll try with the 595.71.05 again but with the kernel parameter”, said me.
I did it the process and all goes well (thanks to initcall_blacklist=sysfb_init). But before of 7.0.9 this parameter don’t worked for me.
Well, now I have fixed my issue. Thanks to every post of this thread.
Regards