Aha! I found it. It was in the Boot Camp control panel. The brightness was all the way down to “dim”, but the weird thing is I know damn well I didn’t open that thing before, so I have no idea who/what told it to dim itself.
Weird.
Excellent!
Yeah, I’m a bit perplexed, also. I do know that there is a bug with iMac not saving your dimming settings all the time, but I don’t think that was your problem. Perhaps some little gremlins were playing with your computer when you were away from it...
Cheers