Should Set BootROM is 138.0.0.0.0 or 140.0.0.0.0 , For macOS, Modify VBIOS Serial to 113-4E353BU-O4E (Samsung) 113-4E3531U-O4V (Hynix) 113-4E353BU-O50 (Micron) (Serial 113-*E353**-*** is almost OK, 113-*E387**-*** is probably OK. Do NOT Use 113-*E366**-*** For Serial. for example, 113-1E3660U-O51, 113-3E366DU-S4Y are NG to use Serial. ) and For Windows, should use \config.h of 113-3E366DU-S4Y (Samsung,Hynix) 113-4E353WU-O67 (Hynix) 113-BE366EU-Z48 (Micron) For correctly working RX470/480/570/580, Should Set as "Radeon.png" (&See example.png, https://forums.macrumors.com/threads/turn-a-new-sapphire-rx580-pulse-into-the-mac-edition-card.2101909/page-15#post-27274027) or recommend to Use Kext relating Radeon from "10.14.0" or "10.14.5 developer beta 4". in Terminal: defaults write com.apple.AppleGVA forceATI -boolean YES defaults write com.apple.AppleGVA forceSWDecoder -boolean NO sudo update_dyld_shared_cache -force REBOOT Or sudo nvram boot-args="shikigva=96 shiki-id=Mac-7BA5B2D9E42DDD94" Or sudo nvram boot-args="shikigva=61 shiki-id=Mac-7BA5B2D9E42DDD94" Or sudo nvram boot-args="shikigva=41 shiki-id=Mac-7BA5B2D9E42DDD94" if recognize wrong, try to change Board-ID basically "Mac-7BA5B2D9E42DDD94" or "Mac-F221BEC8" (because iMac19,1,iMac19,2 uses same properties of Mac5,1)