Twice today this happened. Both times I was playing a game, one a jigsaw puzzle game and one a needle work paint game. All of a sudden my screen went fuzzy (like static) and then my computer shut down and restarted itself. I lost my game progress but my Firefox tabs were still open.

Any idea?

Could be the power supply is having issues. Maybe overheating.

I'm also guessing power supply issues. However, the fuzzy/static screen also makes me think a possibly failing video card. You can check your interior temps with something like Speccy, which is free software. I use it and it's really easy to use. It's from the same folks who make CCleaner.

https://www.ccleaner.com/speccy

Thank you both.

I have the free version of Speccy but I always forget about it. I'll check it out and keep an eye on the temps.

oldbroad, if the inside of your computer looks like mine, it probably has a lot of dust and cat hair. Check your intake and outflow vents too. I don't "think" temps are your problem, but it's always good to check.

I know without doubt that it is dusty inside.

I'm sure mine is worse!!