Fn keys to adjust brightness not working on Samsung R540 with Ubuntu 14.04 and in India GT330M

Solution 1:

HOW I SOLVED IT

note: if you havent installed nvidia driver. Install it before you continue this.

in terminal

# nvidia-xconfig

this creates /etc/X11/xorg.conf . edit it.

# sudo su  // become root
# gedit /etc/X11/xorg.conf 

find Section "device" in text. add this line

Option "RegistryDwords" "EnableBrightnessControl=1"

so it shold look like it on the rightside

from this                        TO   this     
Section "Device"                  | Section "Device"
 Identifier "Device0"             |   Identifier  "Device0"
 Driver     "nvidia"              |   Driver      "nvidia"
 VendorName "NVIDIA Corporation"  |   VendorName  "NVIDIA Corporation"
                                  |   Option "RegistryDwords" "EnableBrightnessControl=1"
EndSection                        | EndSection

save changes (ctrl+S).
log out. log in.

we are done!! now Fn + Up,Down is adjusting the brightness.