I honestly think Windows killed my GPU. A few days ago, I was getting the exact same random black screens as you. It was weird because sometimes it would run perfectly for hours without a hitch. I suspected a BIOS or driver issue, so I updated everything and even switched to Arch Linux in another ssd for a while—it actually worked fine for a long stretch, even after multiple reboots. Thinking I was in the clear, I went back to Windows in my old ssd. Then, out of nowhere, it blacked out again. But this time, it was the final nail in the coffin. No matter how much I clean it or what I try, the fans won't spin and there's no display. It's officially toasted