Alright I'm still having problems.
I've flashed to BIOS 902 and tried known stable 3.4Ghz settings (specifically for the 902 BIOS) for the current older GSKILL PI Black's I have and whilst I have no more blue screens it fails P95 Blend+UT2004 after around an hour, previously this setup lasted 16Hrs until I stopped the test.

I think the reason the blue screens are fixed is that the 1002 BIOS flash was borked.
However there is defiantly a hardware problem going on, but I'm not sure how to isolate if its the CPU or the motherboard or even the PSU.