To my surprise smOS is so versatile that my mining rig, over 4 years old, has stopped hanging one of the GPU's.
I am assuming that it is my PowerColor Red Dragon card, these cards are literally the worst RX 470 card money can buy, don't do it. This aside, smOS has stopped that GPU from hanging. I can't tell if linux and windows identify GPU in the same order, but it seems to be that card.
(2 newer cards resting on a box with a replacement riser just in case.)
Thanks smOS
P.S. the overall running temperature us lower than windows, as well as average fan speed.