Ubuntu 12.04 laptop cannot adjust screen brightness NVIDIA dual graphics card Bumblebee black screen cannot be started

sudo add-apt-repository ppa:bumblebee/stablesudo add-apt-repository ppa:ubuntu-x-swat/x-updatessudo apt-get updatesudo apt-get install bumblebeesudo apt-get install bumblebee-nvidia sudo reboot

The above command is to install bumbleebee

Run the following command:

lspci |grep VGA

If the output is similar to the two rows:

00:02. 0 VGA compatible Controller: Intel Corporation 2nd generation core processor family integrated graphics controller (Rev 09)
0:00. 0 VGA compatible Controller: NVIDIA Corporation device 0de9 (Rev
Ff)

N cards are successfully switched off.

Then configure the notebook FN to adjust the brightness

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Open the configuration file of grub2

sudo vi /etc/default/grub

Set

Grub_cmdline_linux = ""

Change

Grub_cmdline_linux = "acpi_backlight = vendor"

Then upgrade gurb

sudo update-grub

Run the following command to adjust the brightness:

sudo suecho 500 > /sys/class/backlight/intel_backlight/brightness

If the screen brightness changes, the operation is successful, and the FN button is set.

echo 'echo 500 > /sys/class/backlight/intel_backlight/brightness' > /etc/rc.localsudo reboot

..
In addition, because Bumblebee does not support the latest Ubuntu 12.04 kernel, some systems will not be able to start on a black screen after it is installed. When xwindows fails, the solution is to uninstall all nivdia-related files and Bumblebee.

sudo apt-get remove nvidia-*

sudo apt-get remove bumblebee

sudo apt-get install linux-headers-generic
Then reinstall bumblebee (a post is posted on the ask UBUNTU Forum). please google it on your own.Http://askubuntu.com/questions/215146/ubuntu-12-10-nvidia-gt555m-bumblebee