I searched for days and tried everything that seemed like a solution, but I'm slowly giving up hope of getting my rig to work. I have mined perfectly in 2015 with 280x cards, but for some reason I can not get rx 480 cards to behave.
I can mine without issues when inserting only 1 GPU either directly onto the MB or with a powered riser. Only when inserting 2 or more GPU's with risers, added card(s) drops to 0MH/s within seconds, but only for the GPU(s) that are not in the "main" PCI-e slot. The "main" GPU never causes the crash. After halting to 0MH/s my rig freezes. When I notice my hashing going down to 0MH/s on a card and I can still quickly close the miner, my catalyst driver crashes.
At the time of freezing, GPU-z reads 0% on memory controller load on the crashed card(s).
Gigabyte 990FXA-UD5 (newest firmware)
Amd sempron 145
4x Asus RX 480 Dual OC 8GB
2x4 GB Ram
Windows 10 64bit pro
Virtual memory set to 16gb
Powered risers rev006
Current driver: 16.9.1
Mining ETH with Claymore 9.4
GPU temps are 65°C
I have also tested on a Asrock Z97 Extreme 4 motherboard (newest firmware), tried different risers (even old ribbon risers), all with similar results.
I have tried setting PCI-e gen to auto/1/2/3 on the Z97 mobo, the 990FXA doesn't even have this option.
I tried different miners (qtminer)
Is there anyone that can help me with some advice?