Does anyone know which is the last good Polaris driver version before they destroyed performance when re-writing for the 5700XT?
Destroyed performance? I'm running 19.8.1 on all my rigs and my performance is uneffected, if anything they're more stable across 15 Polaris model cards, 580's, 570's, 8GB and 4GB....
Not sure where you're getting the hit.
As for the hanging on closing the miner mentioned above... I've seen that when under volting the cards, or trying to push the clock to high, however I do not experience hanging of the miner that often.
I have 4 of my own rigs, and have provided support on well over 25 others... and that ranges on memory through all memory types.
Very interesting you're experiencing it consistently.