CPU: 3700X (also tested with 1400X)
MOBO: ASUS Prime X570-Pro (also tested with B550 Aorus M and RMA'd ASUS X370 Crosshair VI Hero, all with latest BIOS'es)
RAM: G.Skill Ripjaws V 32GB 3200MHz (also tested with 16GB kit of same model and without XMP for both)
PSU: Corsair RM850X (also tested with Seasonic G550, separate GPU PCIe power cables for both)
OS: Windows 10 Professional (latest as of posting), temporarily Pop_OS! 20.04 for testing.
GPU: Gigabyte Vega 64 Gaming OC (latest 2020 drivers tested, 19.12.1 drivers tested, 20.Q3.1 Pro drivers tested, Linux used AMDGPU)
When playing the whole system will suddenly freeze, audio goes brrrrr and sometimes GPU fans max out. With normal gaming drivers I have to power cycle the system multiple times until I get the mobo to start up in fail-safe mode to get it back into Windows, but with Pro drivers it will atleast restart on it's own. Some rare days I can actually play for a whole afternoon without issues, but those are rare.
I'm the 3rd owner of the card, the previous owners had no issues like I have. The only difference between 2nd owners and my system is that he played in 1080p, while I got a 4K monitor with Freesync. I thought it might be load issue, but even with low settings and limiting power to -50% setting it still freezes, the card didn't even go above 65°C and hotspot stayed at ~82°C.
I've checked the event log and normally there is just complaints from Windows for not shutting down properly, but lately I got a Cache Hierarchy Error (APIC ID: 1). It is not the CPU or RAM, I've tried whole another system with the same issues.
There is a single game where the whole system will totally freeze consistently: Exo One: Prologue, right where the transition from intro cutscene to the game happens.
THINGS I'VE TRIED
Setting VRAM min/max to highest state, lowering power limit, disabling Freesync and other features like Chill, new mobo, reinstall Windows, whole another system, replacing thermal paste and pads, trying Linux and updating GPU VBIOS to latest one from manufacturer site.
The only way the system has stayed stable was when using Linux, Pop_OS 20.04 to be more specific. I could play for hours without freezing issues.