ROMs differ between RX 480 and Fury X, but they are sort of the same if you get what I mean
All AMD ROMs are AtomBios, see heading in Fiji bios mod OP
. Basic ROM structure is 3 areas, Bios header > Legacy section > UEFI/GOP module.
Through investigations by members/myself we learnt a lot from Hawaii bios mod
, then this "experience" was great for Fiji bios mod as well. At first with Hawaii there was a lot of manual investigation (early 2015), by the time we got in the swing of things we learnt Linux driver has a lot of information on structure of ROMs and as open source there to see
was handy plus other parts
The Legacy section contains data/command tables, you can take like GPU ROMs and will find the command tables are identical, only certain data tables change due to say PCB VRM components/config, cooler used, etc. Some of the data tables are the same structurally between even GPUs, for example the PowerPlay in Tonga was also used in Fiji and it's the same one in Polaris
. Obviously data values differ, view this link
for structure of PowerPlay, in this post
you will see image of it being used to mark header.
I don't know the exact reason for why the UEFI/GOP module become universal. I know AMD ROMs are Hybrid ROMs, the Legacy ROM sets card up, if a UEFI/GOP is in ROM card becomes UEFI compatible if not it is Legacy. I'd assume all they are doing is incrementing support for a new GPU in each version. I recall seeing an image where a member had extracted IDs within the UEFI/GOP module, but I can't find it now.
The voltage control chip IR3567B was used on Hawaii, Fiji and Polaris. So some of the mapping done by ROM compares and info leaks by The Stilt and another few sources, allowing us meddling of it
(WIP progress still
If your card was dual bios I would have defo given you the ROM by now, as I'm pretty certain all is fine, but as I do not have enough experience about the UEFI section I wish to have it confirmed
.Edited by gupsterg - 10/16/16 at 2:46pm