I run it undervolted and Overdriven too, 41 mh/s fairly cool no where near its bench limits. It may be the driver so I installed the latest one to do more testing (19.10.1). It happened after I updated both gpu driver and PM but since the switch, this profile used to run absolutely solid. Dialled it back to test more and will see.
Sounds good. Did you flash 64 bios? It'll make a ton of difference in the hash rate. I was able to hit 1125 mhz in mem clock (samsung memory vendor) but it crashed after a while. So settled for 1095 mhz (stable).