(This is a copy of from another forum trying to figure all this out. I was told by Microsoft support to contact Manufactures.)
So to start off with, the PC is a New Build, Specs are :
CPU -AMD Ryzen 7 2700x 3.7GHZ
RAM -2 Sticks of 8g ddr4 3000mhz
GPU -EVGA RTX 2070 XC Ultra Super
PSU - Seasonic 750w Prime 80plus Titanium
MOBO-Asus Prime x470-PRO
CPU Cooler -DEEPCOOL Captain 240 EX
Case -Fractal Meshify C
TL;DR at bottom
After I first booted the PC and installed windows, I proceeded to install all the updates I could think of. I updated Windows till I couldn't update any longer. I downloaded the newest Graphics drivers, then I found the news BIOS version and flashed the BIOS. After all that, I started to install games. The first one I got to play was Borderlands 3 (Which I have read that many ppl have optimization problems with, but this goes beyond one game). I got to play for about 20-30 minutes, then the game crashed. I proceeded to reboot the game and it followed with even shorted times between crashes till it finally rebooted my PC. I then, after a time to allow my time to cry(PC to cool), installed No Man's Sky to see if it was the game or my system. I got the same results. I then did some research. Which had me download some programs.
I installed Core Temp, and EVGA Presision x1 and started monitoring my CPU and GPU temps. Highest CPU Temp I have seen was 51c. Highest GPU temp I saw was 81c. I continued to monitor these thinking it had to be a heat issue. I stopped booting BL3 as the game crashes in seconds now. I instead tried NMS. I got a good 5 minutes of solid play, and noticed the CPU temps stayed in the mid 40s and the GPU temp between 60-70. The GPU memory was around 7k MHz. The GPU clock was showing 1900 MHz. It then crashed and gave me a generic error telling me to visit their site. I spent the next 30 minutes trying to figure out the problem was, and tried one last game.
I tried a less resource heavy game, WoW Classic. I didn't see a difference in temps nor usage, yet I was greeted by a reboot. I have no idea if its a heat problem, bad hardware, faulty software, or a power issue. The PCI-E cable I have to my GPU is a 6pin and 8pin(6+2). The install manual was showing me a input cable that I didnt have(Something to do with the 8 pin having a barn looking hexagon on top of another hexagon on the +2 part, but I only have cable that are square on top of hexagon) , so I used one of the 5 PCI-E cable my PSU gave me.
So I have no idea if that could be it. If you couldn't tell by my explanation of PCI-E cables there at the end, I am not that knowledgeable about these things.
TL;DR- PC crashes/ Reboots. Have newest Graphic drivers, Windows updates, and BIOS updates. Thinking its heating issue. Have monitored temps and from my knowledge, and they are in acceptable range.
ADDED: I now have had my first crash while not gaming. Also I read someone's comment on another post about resetting gpu and RAM. So while doing so, I took my cooler off my cpu to see what the factor paste looked like and saw what looked like a electrical arc of sorts, like current trying to cross between two points. Also the paste on my CPU looked a bit dry and cracked. This doesn't seem healthy.
Thank you for any assistance you may lend