I know this error might have been raised before but am not getting a clear solution.
I updated my old Asus N56V BIOS . To my surprise, the brightness is no longer controllable. The screen has become so so bright , to a point my eyes are struggling.
I also noticed that an error
" acpi has been disabled or is not available on this hardware" is displayed on the BIOS startup.
I tried to log on using an old kernel by setting it as default boot option. The performance of the machine is extremely poor.
Please pass some insights.