Ubuntu – UbuntuGNOME 15.10 64 bit doesn’t shut down


My laptop doesn't entirely shut down. Everything goes black but the screen is still on and I have to force shutdown.

I don't know to which package should I post this bug to. How can I determine this ?

My laptop is an Acer TimeLine X 5820T, 8GB RAM, 240 Kingston SSD, Intel Graphics version and Ubuntu Gnome 15.10 64 bit.

Best Answer

Add a specification to your grub commandline option in the /etc/default/grub config file. This is the option that begins with GRUB_CMDLINE_LINUX_DEFAULT.

Try adding the following reboot=pci to that line. The changes would be:

Change from:


Change to:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash reboot=pci"

After making changes to your grub configuration you will have to run the update command to activate the change:

$ sudo update-grub

(The $ sign is important in the line above. It's indicating a terminal commandline from the user's prompt.)

There are other reboot flags you can test if that one fails. The options includes:

  • warm - don’t set the cold reboot flag
  • cold - set the cold reboot flag
  • bios - reboot by jumping through the BIOS (only for X86_32)
  • smp (reboot by executing reset on BSP or other CPU - only for X86_32)
  • triple - force a triple fault - init
  • kbd - use the keyboard controller. cold reset (default)
  • acpi - use the RESET_REG in the FADT
  • efi - use efi reset_system runtime service
  • pci - use the so-called “PCI reset register”, CF9
  • force - avoid anything that could hang

Also, you can try multiple parameters at the same time such as:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash reboot=warm,cold,bios,smp,triple,kbd,acpi,efi,pci,force"

Other details can be found at:


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