sudo tail -f /var/log/messages.log
Jul  2 02:23:23 localhost kernel: [ 1922.816847] NVRM: loading NVIDIA UNIX x86_64 Kernel Module  302.17  Tue Jun 12 16:03:22 PDT 2012
Jul  2 02:23:23 localhost acpid: client connected from 3628[0:999]
Jul  2 02:23:23 localhost acpid: 1 client rule loaded
Jul  2 02:23:28 localhost acpid: client connected from 3628[0:999]
Jul  2 02:23:28 localhost acpid: 1 client rule loaded
Jul  2 02:23:34 localhost kernel: [ 1933.457643] bbswitch: disabling discrete graphics
Jul  2 02:23:34 localhost kernel: [ 1933.469738] pci 0000:01:00.0: Refused to change power state, currently in D0
Jul  2 02:23:34 localhost kernel: [ 1933.471793] pci 0000:01:00.0: power state changed by ACPI to D3
Jul  2 02:23:40 localhost acpid: client 3628[0:999] has disconnected
Jul  2 02:23:40 localhost acpid: client 3628[0:999] has disconnected