I built a friend an AMD Ryaen 2700 CPU, AsRock B450 motherboard, 2 8GB Viper memory sticks, an XPG 512 GB NVME SSD, and an XFX RX-560 video card. The system ran great for almost a year and then wouldn't boot. I told my friend to rescocket the memory and SSD and it appeared that resocketing the NVME SSD resolved the problem. Then it ran for a few months until recently it started randomly crashing again. He did some investigation, we now live 130 miles apart rather than 3, and thought it might be overheating of the video card because he noted the fan was not on. However the fan is temperature activated which I figured out and so that probably wasn't the cause. He bought another used card of the same model off eBay for $200, the original was $100 new, and that did not correct the problem. I also had him take out one stick of RAM at a time but still had the problem it seemed. He finally drove over and left it with me for a couple of days last week and I completely reinstalled windows with the "newer" video card using the 1903 build and then upgrading immediately to the newest build. I ran into no problems pushing the machine through everything that a clean installation does. After I downloaded a couple of stress tests and ran one for an hour with no problems. I did install a 3D video stress test and watched the GPU heat up and the fan work, with both cards, and it ran fine but on one run the machine locked with some kind of driver error message. He took the machine home and just wrote to tell me it has locked up a couple of times on him. I am going to see if he wants me to trade him memory from my machine and see what happens. I am waiting for more information about anything specific during the crashes he might have noticed. So I am stumped and limited in what parts I can change to test it. Does anyone with experience have best guess suggestions what to try to resolve this irritating problem? Thanks for any and all help.