How to set brightness in Linux.
Use this:
cat /sys/class/backlight/intel_backlight/max_brightness
You could try adding a line to /etc/rc.local that will set the desired brightness level. To edit the file, run
gksudo leafpad /etc/rc.local
and add the following
echo X > /sys/class/backlight/intel_backlight/brightness
so that the end result looks like this
#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
echo X > /sys/class/backlight/intel_backlight/brightness
exit 0
Substitute the X by the desired brightness level.
http://askubuntu.com/questions/151651/brightness-is-reset-to-maximum-on-every-restart
https://sites.google.com/site/easylinuxtipsproject/display
http://www.techques.com/question/24-3841/Desktop-doesn%27t-remember-brightness-settings-after-a-reboot