Not sure if it's related, but according to the event viewer, my system had 2 critical errors (41) last night in the Kernel-power source. The explanation is "The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly."
I always shut down with the proper sequence, so I'm not sure why this would happen. I actually let my computer run overnight, but I had reboot several times last evening.