If you have a new laptop most probably you’ll run into a lot of problems while installing Linux like the over heating issue. The latest Ubuntu 12.04 and other Linux distributions with the kernel 3.4 have fixed most of these heating issues and we showed you how to fix the remaining issue which caused due to switchable graphics. Apart from that, there’s another issue that we need to fix. The screen brightness!
Normally, you can adjust the brightness through your keyboard shortcuts or through “Brightness and Lock” settings. But for some people, this won’t work! Specially for people with switchable graphics.
Earlier, I used to fix this by giving the brightness value I need during the startup (using the rc.local file). But this is a workaround and you need to restart every time you need to adjust the brightness.
Trying to fix the issues, I just looked at the “cd /sys/class/backlight/” folder and there we have a problem. There are several VGAs in this folder and the system is not editing the right “brightness” file!
To fix this, we need to add a simple option to GRUB which will prevent the ACPI backlight driver from starting and letting the laptop specific drivers to handle the job. How to do it? Here’s how…
- Open the grub configuration file using Gedit (If you are familiar with nano you can use it) (Run the command on a terminal)
sudo gedit /etc/default/grub
- Now, add acpi_backlight=vendor to the line GRUB_CMDLINE_LINUX=”" like this :
- Next save the file and run the following command to update Grub:
Now restart and all your problems will be solved! Now special thanks should go for biodiesel-bri in the Ubuntu forum for finding this fix! Did it work? Then go and thank him!