I have a Macbook2,1 with Ubuntu 12.04. When I start the computer the back light is on and I can see all of the boot stuff. Once the GUI begins to start up the backlight is turned completely off and I can not see anything. I do however hear the little ubuntu drum beat, can then type my password and log on. Once I have done this I can then use the brightness buttons to turn the brightness back up but the logon screen is always just blackness.
I can control the brightness from the command line using
echo 500 | sudo tee /sys/class/backlight/intel_video/brightness
and I put this line into /etc/rc.local before the exit 0 but this doesnt do anything. How can I get the brightness back up when the GUI starts up?