Kernel-core-5.15.5-200/201 main display dimmed by 50%

I have recently updated thru kernels kernel-core-5.15.5-20[0,1].fc35.x86_64, and have had the main display in my laptop dim by 50%. Laptop hardware keys can only increase to approximately 70%. brightnessctl command won’t push the display any further either. I haven’t found anything on line, or in this forum that covers the topic with THIS release. I’m currently running kernel-core-5.14.18-300.fc35.x86_64 as it does not exhibit the problem. I’m new to the site as I haven’t had any issues with Fedora that haven’t been fixable w/o a little bit of research online.
Thank you very much!

You could check your maximum brightness by using cat /sys/class/backlight/*/max_brightness

Then you could also change manually the brightness. First use root user on terminal with sudo su. Then change the value of brightness between 0 to the value you found on max_brightness above. Let say your maximum brightness are 225 then after running sudo su use echo 100 > /sys/class/backlight/*/brightness.

The * is arbitrary since for each system will have different directory depend of graphic card being used. On my system it amdgpu_bl0. It should different since you are using Nvidia Quadro.

Beware not to change the value of max_brightness since I believe the driver maintainer must be have the good reason to set a certain value on there to protect your hardware.

Thank you very much for your response, I checked out my /sys/class/backlight/*/brightness files – max is set to 100. I will
see if the values change when I boot to the more recent 5.15.5-200/1 kernels.
I will also look into installing the Nvidia drivers, as they are not currently installed.

The solution to the problem was to install the Nvidia drivers per:

Thank you for your help!

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