I don't know if it works with MOD bios. I don't mess around with that - maybe someone else knows. It works just fine with RX480's. Here's a picture of Claymore 11.1 linux on Ubuntu 16.04 LTS using 6 RX480's:
>img clipped<
did you ever tried Optiminer on Ubuntu 16.04? People get 280-290 H/s on RX480 AFTER fees, not before (what you are posting).
Small difference, but still.
I get 305 per RX480 with optiminer
I have 18 RX480, do the maths, its a huge difference.