I just installed Ubuntu 12.04 and everything seemed to go correctly except that the during the installation the screen was very dim, and i just kept going with the installation. So then I finished the installation, and updated a bunch of stuff when prompted; So now I can finally get to changing the screen brightness option and the slider is all the way up, yet it looks as if the slider is all the way down, So then I went go ahead and turned off the dim option. I exited with the the slider all the way up, and the dimmer off, and nothing happened. I rechecked and it still says that the screen brightness is all the way up, yet it is still very dim. I have a Acer Laptop, I installed it to keep windows 7. Also I looked around and tried "try this
open your terminal and type this sudo gedit /etc/default/grub and find a line GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash acpi_backlight=vendor“ and change it to like that . then close the editor and do sudo update-grub and give a restart . check it out now ."
Nothing changed after doing all of it, Please Help!