Right before bed each night, I restart my computer, so everything's fresh and ready for the next day.
The computer is configured to go to sleep after three hours of inactivity. Normally the antivirus runs at 1:30, unless it's gone to sleep, and if sleeps before antivirus (Avast!) it will run as soon as the computer wakes.
This morning, the lights and fan were on, but the computer was unresponsive. Jiggling the mouse, pressing keys, ctrl/alt/delete, nothing worked. Turning the monitor off and on showed "no signal" to the monitor. Pressing the restart button on the case got no response. So did holding down the power button for 30 seconds (normally, even with true issues, doing this will turn the computer off after five seconds).
I turned the computer off on the back of the case, and when I turned it on, everything started normally, except that I got the black and white screen mentioning an abnormal termination and asking if I wanted to start normally, or try a repair.
I picked "start normally," got to the login screen, logged in, and I used the computer normally and everything seemed to work fine.
The slightly odd things I noticed though:
- The event log showed no activity between 10:18 last night and 6:46 this morning - usually at least there's a computer going to sleep and computer waking up notice.
- The antivirus didn't run last night, and it didn't automatically start this morning, although I started it manually this morning and it ran fine to a successful complete scan, and it did automatically update its definitions as soon as the computer booted.
The only event log error going back several weeks was the power error logged this morning, when I turned the computer off by the power supply switch.
I honestly think that sometimes "once in a blue moon" odd events happen, so I'm not too too worried. As I left the room last night, the normal blue Windows shutdown screens were on, so the computer was shutting down normally. I'm wondering if it's possible that the normal shutdown sequence never completed, thus no BIOS or boot sequence, and the computer was just sitting there using power.