BSOD - usually under low load i.e. youtube playback in chrome

Thought I'd give an update as I have solved this. I returned RMA'd my CPU. No crashes with the replacement AMD sent.
Thanks for your time anyhow!

I put off return for a while as I couldn't be bothered with the hassle. But was fairly painless other than the return paperwork missing some customs declaration required now that blighty has left the EU, but managed to resolve via email. I have been using that for a while now and I am now in a crash free state. Took under 2 weeks (and was over the easter weekend) from me sending CPU and getting replacement.

Well, that is very good to hear. I am glad you followed through with the RMA and that the process was not too complex. Thanks for the feedback.