Backlight/Brightness always at 100% NVIDIA RTX 2080 Mobile 535.154.05, Linux Mint 21.3 (Ubuntu 22.04)

Tried the 545 driver today. No luck and I also got the screen flickering/black screen issue with VRR enabled.

I also want to test the stable 550 drivers, but I can´t select the drivers from

ubuntu-drivers list

Do I have to wait or it it somehow possible to install the drivers manually without breaking the os?