How can I change the screen brightness of my laptop in ubuntu?

Question

I have an acer aspire 5749 laptop with the latest version of Ubuntu (12.04, I think), so when I change the brightness using the hotkey, the brightness panel changes, but in fact the brightness remains the same. pleaze help me.

Answer 1

sudo gedit /etc/default/grub

And then enter the root password and insert the following lines:

 GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor" GRUB_CMDLINE_LINUX="acpi_osi=Linux" 

Save and exit.

sudo update-grub

Restart the laptop, and then it will work using the "Fn" + left and right arrows.

Answer 2

I also have an acer aspire series laptop, and the hot keys do not work, so you can change it by running the command sudo setpci -s 00:02.0 f4.b=00 , here you can enter a value from 00 to ff in hexadecimal format, [00 = bright and ff = dim]

for more information, go to the following link: http://daksh21ubuntu.blogspot.in/2011/12/how-to-increasedecrease-brightness-on.html

Answer 3

Okay, so before anyone comes across

 sudo update-grub 

Recent versions of ubuntu use grub2

So please use:

 sudo update-grub2 

If you do not, your system will not boot, and you must figure it out.

Answer 4

install xbacklight

 sudo apt-get install xbacklight 

then dim

 xbacklight -dec {any value between 0-100} 

to increase brightness

 xbacklight -inc {any value between 0-100} 

Answer 5

I am on Ubuntu 16.04 and use Nuvo. I solved this problem:

• In the terminal type, sudo gedit /etc/default/grub .
• Find the line GRUB_CMDLINE_LINUX_DEFAULT and add acpi_osi=Linux acpi_backlight=native inside "". (If this does not work, try "vendor" or "video" instead of native (of course, without quotes)).
• Now run sudo update-grub

Answer 6

This does not make your function keys brightness, but a workaround.

Install a brightness controller with the following commands:

 sudo add-apt-repository ppa:apandada1/brightness-controller sudo apt-get update 

For version 1 with support for up to 4 monitors:

 sudo apt-get install brightness-controller-simple 

For version 2 with support for Multi-Monitor and other functions:

 sudo apt-get install brightness-controller