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I can't restart my laptop under Ubuntu 12.04 and the screen turns black with no response after clicking the Restart button.

How do I fix it?

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up vote 9 down vote accepted

Open the terminal and edit this /etc/default/grub file under Ubuntu 12.04

 sudo gedit /etc/default/grub

Find now this line:


enter image description here

Replace it with this one:


enter image description here

Save your file and close, then update Grub with this command:

sudo update-grub

Reboot your system, then try to restart your system to see if it works or not. If this is not working for you, repeat the same steps and try one of these lines instead:






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pci worked for a L502X Dell 15 XPS. Finally! – partofthething Oct 30 '15 at 3:46

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