PCs are not 100% reliable and upsets like this, cleared up by pressing buttons or reboots do happen. Since what caused it is gone there is nothing to diagnose.
Bob
Hi
I was watching a movie, suddenly laptops screen and sound went off. I pressed power button multiple times ,but there was no response. I thought the system might be ON still, so I pressed power button for few seconds then released and pressed it again. Laptop was back to normal. Can anybody diagnose what happened?
Thank you

Chowhound
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