Brightness on laptop doesn't change

[GhostToast]

Hi all,

I recently installed Ubuntu 10.04 LTS on my ASUS UL20A-A1 laptop through Wubi. I am loving it so far but there is one really annoying issue. Whenever I try to adjust my screen brightness by pressing Fn>F5/F6, the brightness meter on the top flashes, and the brightness doesn't change, not even when I plug in my laptop. And after I try adjusting the brightness once, the brightness meter keeps popping up randomly without my pressing of the button, and there is no way to stop it popping up. This is really irritating and I really want to use Ubuntu but this is a serious problem for me. Does anybody know how to fix this?

Thanks!

-GhostToast

[KlavKalashj]

Hi all,

I recently installed Ubuntu 10.04 LTS on my ASUS UL20A-A1 laptop through Wubi. I am loving it so far but there is one really annoying issue. Whenever I try to adjust my screen brightness by pressing Fn>F5/F6, the brightness meter on the top flashes, and the brightness doesn't change, not even when I plug in my laptop. And after I try adjusting the brightness once, the brightness meter keeps popping up randomly without my pressing of the button, and there is no way to stop it popping up. This is really irritating and I really want to use Ubuntu but this is a serious problem for me. Does anybody know how to fix this?

Thanks!

-GhostToast

This is a known bug, and it also affects me on my UL30A. You can find progress info here: https://bugs.launchpad.net/ubuntu/+s...ux/+bug/543294

Please write there if you have anything to add.

[KlavKalashj]

Dude, you are lucky! I just checked the bug report again, and someone posted a workaround which worked perfectly! Do it like this:

1. Open a terminal (Program - Accessories - Terminal)
2. Type in "sudo gedit /etc/default/grub" (without the "")
3. Find the line that says: GRUB_CMDLINE_LINUX="quiet splash"
4. Edit it so it says: GRUB_CMDLINE_LINUX="quiet splash acpi_backlight=vendor"
5. Save and exit
6. Run the command "sudo update-grub" (again without quotes of course)
7. Reboot and enjoy!

It's very easy and on my ul30a it worked like a charm!

[kjurkic]

Thank you very much KlavKalashj

I used this fix for Asus EEEPC 1005PE and it worked.

I have years of experience with various linux distros, but would have taken a long time to figure that one out....its little problems like this that make Ubuntu or linux in general a hard-sell to newbies, who don't really car about OS's, they just want it to work without having to trouble-shoot.

regards
Ken

[Donalt2010]

This actually didnt work for me for some reason, done exactly as it says and its made no difference

[rs87424]

I have an Acer Aspire 4810 and I also didn't see any change in this modification... are you able to use the "Fn" key to adjust your brightness?

[D4v1dw1r7h]

Dude, you are lucky! I just checked the bug report again, and someone posted a workaround which worked perfectly! Do it like this:

1. Open a terminal (Program - Accessories - Terminal)
2. Type in "sudo gedit /etc/default/grub" (without the "")
3. Find the line that says: GRUB_CMDLINE_LINUX="quiet splash"
4. Edit it so it says: GRUB_CMDLINE_LINUX="quiet splash acpi_backlight=vendor"
5. Save and exit
6. Run the command "sudo update-grub" (again without quotes of course)
7. Reboot and enjoy!

It's very easy and on my ul30a it worked like a charm!

This worked perfectly on my ul20a too!!

[burrhead1]

Yee Haw Pa, it worked! There was a difference in line 4 of the instructions and the line in the directory that appeared after running the line 3 command; the word DEFAULT was between LINUX and the = sign. Ran the line 4 command with out DEFAULT in it and it didn't work. Ran line 4 again with DEFAULT in the command and it worked like a charm. Now I won't have to wear sun shades at night when using Linux.
This is the best O/S forum I've ever been on. Thanks to all who contributed to solving my problem.

[travissparks1307]

I just booted up my Acer Aspire 5734Z and the screen was way too dark. Brightness controls were doing nothing. I did what the workaround said, rebooted, and BAM! Oh so beautiful. Thank you so very very much.

Running Ubuntu 10.10

[ikiini]

I have a t410 with a dedicated nvidia quadro nvs 3100m card. This fix is not working for me. the brightness is set only if I set it, and restart the machine. it restart with the brightness level i set before restarting. I tried a lot of things, but no luck. Any other solutions I an attempt? or somewhere I can check logs?

I am running 10.10