11 down vote In my case these simple steps worked for me fine: Press Ctrl+Alt+T to go to a terminal and type: sudo gedit /etc/default/grub This will open the grub config file. Change the line: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=force apm=power_off" Then save & close it. Type in the same terminal: sudo gedit /etc/modules This will open the modules config, just add the following: apm power_off=1 and save the file. Next type in the terminal: sudo update-grub