I've tried 4.9b now with driver 19.12.3 and it says unknown openCL driver and hangs when mining about 15 seconds (totaly freeze, cut the power is the only solution)
Reverted back to 19.9.2 driver and it mines at about 20 minutes, then hang and reboots itself. About 0,3% better hashrate than 4.7c (cant use 4.8c at all)

No logging.

Hardware:
Motherboard: Asus B250 Mining Expert
CPU: i5 6500
RAM: 8gb
Virual memory: 64gb
Gpu's (in order in miner): RX470,RX470,RX580,RX580,Vii,RX470,RX470,RX470,RX580,RX470

Conf for cards:
-cclock 1240,1240,1250,1250,1830,1240,1240,1240,1220,1240
-mclock 2150,2150,2150,2150,1030,2150,2150,2150,2120,2150
-cvddc 930,890,890,930,970,890,930,900,950,900
-mvddc 935,900,910,930,950,900,930,900,950,900
-clKernel 1
-mi 14
-amd
-acm
-cdm 2

Is it something there that's not compatible with 4.9b?

Edit: over an hour now with 4.9b without issues. 19.9.2 driver, still can't use 19.12.3.