@_kabal_
So interestingly enough I decided to download and run OCCT for the fun of it and it appears that the Linpack test that it runs unearthed some stability issues with my RAM that was not being detected by Ryzen Master, Memtest86 or Windows Memory Diagnostic.
The only symptoms I had was that, every now and again I would get a crash in Palworld, but I put it down to it being an Early Access game and just overall pretty buggy so I paid it no mind as I haven't had any other issues.
OCCT gave me errors within three minutes of running it. I reset things to default in my BIOS (CO, PBO, RAM timings, etc.) and then slowly brought things up one by one. It seems that I can get it stable at 3333MHz but at 3400 it starts to give errors again. I've tried upping the voltage slightly, but for now I am keeping it at 3333MHz until I can find some time and sit down and test them stick by stick and see what's what.
It could be that 4x 8GB sticks is putting too much load on the IMC, or maybe I actually have a bad module, but further analysis is required. If I get time tonight or this weekend I will fiddle some more and let you know.
I just wanted to warn you about my findings before you commit to saying yes to a new pair from the retailer.