I am using an Dell Latitude D830 with Ubuntu 12.04. Now, when I turn off the pc, Ubuntu doesn't halt completely sometimes. I think that is due to the latest Nvidia drivers, because in the past with Ubuntu 10.10 I installed the latest drivers released by nvidia and I had the same problem. By now, "messages" file / var / log is always empty. My video card is: NVIDIA Corporation G86M [Quadro NVS 135M] PC will not turn off even with "halt -p".
May be related to this bug seen on Dell m1330, though only seen if using a 32 bit install & nvidia drivers 295.XX - https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers/+bug/940564
Similar question here - Shutdown issues on my Dell XPS M1530
Possible solution other than going back to nouveau or downgrading to nvidia driver 290.20 - Dell Studio 1569 Cannot Shutdown in Ubuntu 11.10 or 12.04
I think I solved it by edditing the reboot options in the grub file. How? just edit /etc/default/grub and search for the line GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" and add the ACPI option force, to become GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=force" This did the work for me. Hope it helps you guys too.
protected by Community♦ May 3 '12 at 11:26
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