I've installed Ubuntu 12.04 on my Toshiba Satellite L645D and the screen brightness does not work, any suggestions??? please help!!
You might want to edit your xorg.conf configuration. In a terminal, type:
This will make a backup of your xorg.conf file - just in case :) That being done, type:
and under Section "Device" add the following line:
Save and reboot.
Perhaps this already does the trick. In that case, congratulations!