You can mix Fury and Polaris cards, but Fury will not work with 100% speed. Either put these cards to different rigs to avoid mixing, or use Linux.
ASM mode do not work with r9 Nano with any driver from 16.9.2+(first driver for rx 480) in windows 7/10. Nano work with driver 16.9.2+ without ASM mode only.
Do you have idea how to run asm mode here? You can see my log file above.