What about when you run every state @ 900? What does hwinfo say about SOC in that case? Or are you sayin opening hwinfo while mining causes a crash? If so, try running hwinfo first
When I run every state @900 it's working (for almost all card execpte bad ones 4/22) and hwinfo is reporting 895mV, 1107 SOC
Ok - one other possibility... somewhere between the TRM implementation, and newer versions of drivers, I feel like Ive seen instances of transitional states lighting up long enough for voltage settings to actually matter. Its possible youre crashing during the p4-p5 transition going from 800 to 1107, as 820mv may be too low (or something like that.)
Try setting either a more graduated voltage list, or set every state to your final voltage (I would suggest the former, in keeping w/ the PPT as floor concept.)
I don't know if this will help, but on some of my Sapphire Radeon RX VEGA 56 8GB if I set Memory P2 below 850 with PP, the card either won't start mining or shut down properly, I have found 880 to work nearly always, there is one "problem child" that requires 900. Of course, YMMV.