Hey! I've bet many have gotten this issue, but I've lately have been experiencing this. Whenever I'm just using my PC in general, almost sometimes a day, the whole display goes dark, and then back to normal state, however my sound has been switched back to default, and I know that It can't be a monitor problem. Its as If I just restarted the computer. I was using YouTube when it happened, and my whole YouTube was black, so I had to close Microsoft Edge and open it up again. I'm not sure what the problem is, I really need help. thank you!