Question Pc crashing, GPU at fault?

Jun 3, 2020
Built a PC 6 months ago, working fine until 2 weeks ago. At that time it began crashing. When it crashes, the whole pc shuts down then immediately turns back on. It does this frequently most of the time (every 15 minutes or so) but has gone as long as 4-6 hours without crashing. This is my main problem, but to complicate things, twice I’ve had a blue screen showing me “SYSTEM_SERVICE_EXCEPTION what failed:dxgkrnl.sys”, and also twice I’ve had the PC freeze to where I had to hold the power button to restart it. I’m assuming these problems are all related, as it’s been working perfectly besides these past two weeks since I built it.

In the system events logs, there are several error messages, with by far the most common one being “A connected hardware error has occurred. Component: PCI Express Endpoint”, which occurs every time the PC shuts down. This is what makes me think it could be a GPU related issue, along with the message I get when I select my GPU in device manager, “DEVICE PCI (a bunch of random numbers and symbols) device requires further installation”

WHAT I HAVE TRIED SO FAR: A reinstall of windows, updating windows, windows memory diagnostic, directx diagnostic, DISM/SFC scans (SFC actually found and repaired corrupted files But did not solve the problem), reinstalled/updated NVidia drivers, updating directx, monitoring temp (CPU is 45-50 idle, 60 when gaming and GPU is in the same range), clearing dust off. I don’t have any onboard graphics or another GPU to slot in to try and isolate the problem and see if it’s my graphics card causing the mess. Can anybody help?

RTX 2080S
Ryzen 3700x
Gigabyte 570x gaming atx
Samsung 1TB SSD
3 case fans, heat sink, an additional fan, and 3 fans On the GPU