Something I noticed when the PC crashes is that it sounds like the fan is running really hard. And then bam! Blue screen of death.
As others have said, it sounds like a possible overheating issue, perhaps due to too much dust inside your card/tower. I had something similar happen a while back because I hadn't cleaned my pc in a long time (because I'm a terrible person); when I ran a game, the already abnormally high temperature would rise, fans would try to compensate, and once it broke 100F the entire thing would shut off. I went and bought some canned/compressed air, blasted the entire rig from the inside and just for good measure decided to blow some air inside the card - and that's when a huge puff of dust came out from inside of it. After that, the problem was resolved, and from then on I started cleaning it at least once a month.
TL;DR - Potential overheating issue, monitor your temps, see if your rig needs cleaning and go from there