That kind of bios is not exist for non ref cards. Each brand , each model number need a different modded bios . If you going to flash a Asus Bios to your XFX card , you going to brick you Card.
I didn't know It would required one for each manufacturer.
Thanks for all the info.
I have different brands of RX 480 total of 3 of them(XFX, Saphire) , and use only one bios, they are behaving correctly. I have them setup in one rig, but have to set the fans manually @80% to have them behave correctly. Only branch I used different' is RX 480 Nitro. I never tried using the the 30Mh Low power bios.