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I recently dual booted my Windows 8 with Ubuntu 13.04. The first thing that came to my notice was that the brightness was too low. I increased the brightness to maximum from system settings, but still, it remains low. I did not face any such issue with Ubuntu 12.10 that I had earlier.

Graphics Card: ATI Radeon 7730M

Laptop Model: Dell Inspiron 15R Turbo

So, is there a way to increase the brightness to the actual maximum?

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which graphics drivers are you using? installing the proprietary drivers may help. sudo apt-get install fglrx or search fglrx in the software centre – amc May 13 '13 at 5:39
I did what you said, the problem didn't get solved, instead my taskbar and dash pane dispaeared! Can I undo it?? – Ranveer May 13 '13 at 6:00
You may need to reboot to ensure the newly installed drivers are loaded correctly. If you still have issues then they can be uninstalled by issuing the command "sudo apt-get purge fglrx" in a terminal. Ctrl+Alt+F1 will let you log into a command line if your graphics are really messed up. Be sure to reboot! – amc May 13 '13 at 6:34
At least this is a known bug:… – YuriC Jun 16 '13 at 17:31
up vote 0 down vote accepted

you may need to use the acpi_osi='!Windows 2012' boot parameter

sudo sed -i "s/quiet splash/quiet splash acpi_osi=\'\!Windows 2012\'/" /etc/default/grub;sudo update-grub;echo 'Reboot to apply'

here is the command to undo that, if it makes it worse or does not do anything

sudo sed -i "s/ acpi_osi=\'\!Windows 2012\'//" /etc/default/grub;sudo update-grub;echo 'Reboot to apply'

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Tried, not woking :( – Ranveer May 13 '13 at 6:19
I have added another workaround. Let us know. – 22lk94k943 only May 13 '13 at 9:25
Working now! Thanks! – Ranveer May 13 '13 at 11:55

It could be possible that you may have to re-install the OS and junk if you are not going to loose a lot of stuff.

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Is there a way around? I have a lot of stuff installed on my PC. – Ranveer May 13 '13 at 6:01

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