Changing the brightness stopped working in 13.10 Saucy Salamander
Solution 1:
the only way to change brightness is to use this command
sudo su
echo 150 > /sys/class/backlight/intel_backlight/brightness
all other solution does not work at the moment. this is not my work around. I don't remember where I found this but it works and hats off to the person who gave this workaround :)
Using Ubuntu 13.10 64Bit Wubi on Lenovo Z570
Solution 2:
If you're using intel video card do:
sudo -H gedit /usr/share/X11/xorg.conf.d/20-intel.conf
Add the following in the empty file then log out and log in again or reboot. That should fix your problem.
Section "Device"
Identifier "card0"
Driver "intel"
Option "Backlight" "intel_backlight"
BusID "PCI:0:2:0"
EndSection
Solution 3:
As Timo Aaltonen (tjaalton) brought to my attention on IRC, this is bug related to the latest drivers nvidia-319-updates
. Reverting back to 304
fixed my problems, although I call this rather a workaround than a fix, as I won't get many of the recent performance improvements of newer drivers.