I'm not able to help you with your issue, but maybe someone or you can help me. I have a msi Rx-480 asusx99 pro/usb3.1 w/i7-6800k that I have never been able to get accelerated. I need to dual boot w/ win10 so flashing the Rx480 to an unrecognized ID is not an option. I had used a radeon HD5450 and a radeon HD5750 as helper cards that successfully had acelleration before adding RX480 to second slot. I had a lot of help from
@gigamax and
@jerryy2345 and
@Ur-Quan but to no avail. I found that bios would not allow me to choose which slot to boot first, so that was out too. I apoligise for piggybacking on your question, but hopefully someone will see the thread activity and help us both out. Also shoutout to
@Mork_vom_Ork for all the efforts on behalf of polaris cards and especially trying to bribe
@slice or any clover dev to help with bypassing the helper card necessity initialization that polaris requires in hackintosh.