Comment 62 for bug 806032

I'm not sure if this is still / again the same problem, but I have a very similar issue on a recently bought Clevo P650RA laptop, running Ubuntu Xenial / 16.04 and the similar bug search when reporting a new bug led me to this issue.

The brightness keys do not work; setting the brightness manually through /sys/class/backlight/intel_backlight works fine.

Probably related: in the BIOS I can select either MSHYBRID or DISCRETE for the GPU, meaning either Optimus-like-technology or DISCRETE only. When using DISCRETE, the brightness keys do work. However, in that case I'm forced to use the Nouveau driver since the nvidia driver will not work anymore. And the nouveau driver makes this laptop crash after a short while, so it's not really a viable alternative.

When running in MSHYBRID, maybe there are more possible connected devices making this bug appear?

There's also some ACPI Warnings in DMESG that may be related. I'll attach the output of dmesg to this message.

Please let me know if I should report a new bug rather than necroposting in this old bug that appears to be resolved long ago. I'd be happy to provide more information if you point me in the right direction for obtaining that information.