Before you do, check your BIOS settings. Overclocking or “XMP” profiles can result in corruption in RAM, even for good sticks. Check that you’re not using a speed over the mobo’s specs and QVL.
You’re using a “gaming” motherboard. I wouldn’t be surprised if it’s set to an XMP profile for the RAM settings.
Memtest86. I think it’s become the new, ‘Have you tried turning it off and back on again’
I have yet to see a board that defaults to using XMP.
Maybe they exist, but I don’t get the impression that it’s common.
I could be wrong, and maybe the idea came from purchasing gaming PCs from sellers that boast the system is already tweaked for performance.
I swear my board went to the max supported speeds for my ram… but it is ecc ram & a halfway server board
Overclocked ECC RAM? 
What is this monstrosity you speak of?
Seems like it could be something similar to this:
https://www.kingston.com/en/memory/search?partid=KTD-PE432ES8/16G
Huh, you learn something new every day.
I think that is the exact dimm I use - yeah, bios just instantly defaulted to 3200MHz. I was also surprised.
*Edit: Correction - that was when I had two dimms, I just checked now that I have 4 & it is at 2933, which is still technically ‘overclocking’ I guess.
A bad memory sttick were the problem. Bought new memory and that fixed the issue (REALLY bad timing to have to buy RAM now).
Thanks for your help, I really appreciate it!
I’m sure @truenas-fan is happy to hear that yet another issue was resolved by running a memtest.
