Hi.
I just added second GPU to my PC.
Sapphire RX480 8GB was the first one, second is XFX RX580 8GB. Both with Samsung memory.
After adding second GPU hashrate dropped significantly from Sapphire. I was able to get (stable) ~29-30.5Mh/s (with a little OCed vram).
Both cards has ~110W power usage (GPU-Z)
Now it's something like:
PS - no, it's not a problem of throttling, it keeps stable 1150MHz.
PS2 - yes, crossfire is disabled
PS3 - yes, both cards are working in 'compute' mode.
PS4 - increasing 'power limit' does literally nothing.
Additional args:
-dcri 30,33 -ethi 8,16
My specs:
Asus Sabertooth 990FX 2.0
FX8350 (tried underclocking/volting it in case of too weak PSU)
PSU - Chieftec 750W
Newest AMD drivers (tried older too, but even newest worked fine before adding 2nd GPU).
Is it normal?
My friend has exactly the same setup (with exactly the same PSU), but he has 2x RX580 (Sapphire with hynix memory and XFX with samsung memory). Everything works fine.