#Screen brightness / backlight on Sony Vaio #Tested series VPCEG
create /usr/share/X11/xorg.conf.d/20-intel.conf
Section "Device"
Identifier "card0"
Driver "intel"
Option "Backlight" "intel_backlight"
BusID "PCI:0:2:0"
EndSection
Add video.use_native_backlight=1
to grub options
Source: http://forums.linuxmint.com/viewtopic.php?f=49&t=165133&start=40 Credit: JeremyB