How to control Brightness on Acer Laptop [duplicate]
I've installed Ubuntu 12.04 in an Acer Timeline X 5830TG and brightness controls were not working (Fn + Key), even the Ubuntu's one.
Solution:
Edit GRUB:
sudo nano /etc/default/grub
change GRUB_CMDLINE_LINUX_DEFAULT to
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"
then:
sudo update-grub
Reboot.
Controls are working.