Contents of '/var/log/syslog': May 21 20:03:56 turing udevd[475]: timeout: killing '/sbin/modprobe -bv acpi:LNXVIDEO:' [497] May 21 20:03:57 turing udevd[475]: '/sbin/modprobe -bv acpi:LNXVIDEO:' [497] terminated by signal 9 (Killed) May 21 20:03:57 turing kernel: [ 77.218818] ACPI Error: Method parse/execution failed [\_SB_.PCI0.PEG0.VGA_.LCD_.NINT] (Node ffff8801c6065870), AE_AML_INFINITE_LOOP (20120320/psparse-536) May 21 20:03:57 turing kernel: [ 77.218828] ACPI Error: Method parse/execution failed [\_SB_.PCI0.PEG0.VGA_.LCD_._BCM] (Node ffff8801c60658e8), AE_AML_INFINITE_LOOP (20120320/psparse-536) May 21 20:03:57 turing kernel: [ 77.218836] ACPI Error: Evaluating _BCM failed (20120320/video-364) Launchpad report: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/994994 Lasted tested upstream kernel: http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.4-precise/
Created attachment 73347 [details] # acpidump > acpidump
BIOS update solved it.