Ok, been a couple of days and so far no more crashes!
This is the longest I’ve been able to go without crashing since this entire shenanigans started. I’ve disconnected the two HDDs, as they weren’t being used for much tbh, and I’ve got a new 1Tb NVME drive coming today that’ll go into my 2nd M2 slot on my motherboard, which should be more than enough for my Steam game catalogue overflow 
Thanks for the replies folks, hopefully the new Zen kernel and mesa drivers appear to have fixed it!
Cool, sounds like it’s gonna be allrgiht! 
Note that HDDs are really good for long-term storage of something, as they live way longer surely you’ll find some use for them as well once 
Aye, they’re still in the machine, I’ve just pulled the cables out of them in the meantime. I think one wasn’t far off falling over anyway (the older 5400 drive), but I definitely don’t need 5+ Tb of space
The new NVME drive coming today should see me through for space ok for the forseeable. The good thing is it means I have no HDDs left in this machine, it’s now all SSDs, which keeps things nice and speedy 
and quiet…
Looks like memory errors to me.
That’s what I had thought originally too, which led to me buying a new set of 2x8Gb sticks to replace the ones I had. Put em in and still had the same errors.
Thankfully now though a new kernel and mesa driver appear to have fixed the issues completely, and I now have a nice 32Gb of ram too
It is, especially after I disconnected my DVD drive, because man that thing was loud on startup lol