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I have an Acer Aspire 6930G with an Nvidia 9600MGS and Ubuntu 12.04 LTS. Every time I turn off my computer and then turn it back on the brightness is always set back at the lowest possible level. I like to use max brightness but the computer keeps reverting back to minimum brightness after I turn it off.

I installed Ubuntu on this computer a week ago and this has been happening since the first day.

Can anyone offer some solutions? I've tried a few and none of them worked for me, that's why I'm asking here

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Could you edit your question with links to the tried solutions? Otherwise people will answer with solutions you may have already tried – Noosrep Mar 12 '14 at 7:31
There were a lot mainly from forum posts ranging from 2010 to 2011. I figured maybe the fixes I tried are outdated. I'm willing to try anything at this stage even if it is the same ting I have tried before. – user257396 Mar 13 '14 at 7:00

You could always try this:

edit /etc/rc.local to insert your preffered value:

sudo gedit /etc/rc.local

and add the following

echo X > /sys/class/backlight/intel_backlight/brightness

replace X by the value of your need

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Alright I explored my sys folder and the chain goes: sys/class/backlight/acer-wmi/brightness. I changed what you said to read: echo 9 > /sys/class/backlight/acer-wmi/brightness and when I restarted and went to settings, the brightness bar was on full but the physical screen brightness was not. I clicked and dragged the slider back a bit and it instantly lit up. So to summarise; when I turn my computer on now the brightness bar appears on full but the actual screen illumination is minimum. Any suggestions? – user257396 Mar 15 '14 at 7:17

This is weird action from some Video cards to solve this problem you can do the following:

First let us check yiour VGA device code

lspci | grep VGA

The device code looks like 00:03.0 for example.

To set brightness

sudo setpci -s '00:03.0' F4.B='xy'

where 00:03.0 is your VGA device code && xy is hexadecimal value of your screen brightness varies between 00 and FF.

Now add this command to the /etc/rc.local file to run always on startup.

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Hi, thank you for answering but can you please explain what you mean when you say 00 and FF? I don't understand what I am supposed to type there. I want the maximum brightness on the computer. – user257396 Mar 15 '14 at 2:08

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