Back in May I was starting to have issues with my GPU. The monitor would suddenly turn black and few seconds later the computer would freeze. It would happen very rarely and after reconnecting the GPU and the cables everything would be fine. I thought it was some loose contact somewhere. But then one day after it happened I couldn't boot into Windows and in BIOS the screen was full of artifacts. My i5-4690k has an integrated GPU, so I could easily confirm it was my GPU, a Sapphire Dual-X R9 270X OC (2 GB) from 2013. It is an old card, but still good enough for me. This happened while I was playing Claw, a 2D platformer from 1997... not a very honorable death for a 2013 card.
I was already looking at the second-hand market and contacted few people to buy a used RX 570, when I read about people baking their GPUs in an oven and fixing it. Since the GPU is 6 years old, out of warranty and obviously broken, and I have an old oven in the garage that is barely ever used, I decided to give it a chance.
I preheated the oven to 190°C, put the GPU board inside and baked it for 8 minutes. Then I opened the oven slowly and let it cool down inside. People warned about being careful not to cool down the GPU too fast, because it could cause cracks in the solder. Also be sure to open all doors and windows, because it will smell of solder.
Since I didn't have thermal paste, for a quick test I put it in the computer without the cooler, I just put a case fan to cool it and was monitoring the temperatures. To my big surprise the artifacts were gone and I could boot to Windows again. Then I started Furmark and it would crash right at the start, even though the temperatures were still low. Luckily after getting thermal paste and mounting the cooler it worked fine. My guess is there is still some bad contact between the GPU chip and the board, but by mounting the cooler and adding pressure the contact is now stable.
It has been three months already and it still works. I have played and finished few games and even ran some benchmarks. Only once did I get that black screen, about a month ago, but it didn't repeat again.