That is an NVRAM chip, even though it's not the BIOS NVRAM chip.
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iM 4,1-14,4 EnableGop: Pre-OpenCore GOP support for EFI-era iMacs and Mac Pros
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Tratkazir_the_1st
macrumors 65816
Well, I believe it will just work for you ... but it's your risk so ...
If you want to be really certain you won't brick it, you need to buy a USB CH341A plus SOIC clip, and you need to practice clipping on to the VBIOS flash chip and reading from it, and really, to be sure, writing back to it what you read from it; i.e. practice removing the graphics card and then reading/writing to its flash using a clip and another computer.
Then you will have a backup and you can basically be sure that you have the technology to restore it to its previous state if needed.
But given the other success stories above, the updated VBIOS should just work...
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FilthyMuppetInnuendo
macrumors regular
I’d like to add (for the sake of SEO and others looking for the information since it’s not in the OP) and say that EnableGOP works perfectly to make a GTX 980 have a pre-boot screen… from its DVI port (if it has one). DisplayPort ports don’t show a pre-boot screen. I also have an HDMI port on this card, but I have nothing to connect to it so I can’t say if it works.
Further, with this modification, you can’t use the pre-boot screen “blind” anymore (that is, holding Option even when you can’t see it and using the arrow keys and Return to select your boot volume, which is what I did for countless years).
Further, with this modification, you can’t use the pre-boot screen “blind” anymore (that is, holding Option even when you can’t see it and using the arrow keys and Return to select your boot volume, which is what I did for countless years).
DIY Monkey
macrumors newbie
I tried this on my AMD Radeon Vii with the Vbios you supplied, and it did not give me an Option key boot screen,
card still worked fine just no Option key boot screen, so I re-flashed it back to its original Vbios,
yes i made a backup with GPUZ before i made any changes.
I had a look for the Vbios at TechPowerup and the only VBios close to "Radeon vii pro" I could find was "Radeon PRO vii", a much later model card, is this the card you meant???
I was using amdvbflash_win_3.15 as it gave me a GUI to work with,
when i tried to use amdvbflash_win_5.0.874 all i got was a command window with no interface.
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Tratkazir_the_1st
macrumors 65816
@DIY Monkey
Do you have EnableGop module in main Mac firmware? This works only in conjunction with it AFAIK.
Do you have EnableGop module in main Mac firmware? This works only in conjunction with it AFAIK.
DIY Monkey
macrumors newbie
Um no i do not, so the Vbios for the Radeon Vii only works with the firmware tweak?
was hoping i would not have to mess with the machine's firmware.
I'm running cMP5,1 with latest firmware 144.0.0.0.0, 6 core 3.46 Xeon, Radeon Vii, 64 gig 1333 mhz memory,
Mojave under Martin Lo’s OCLP config, machine runs great was just hoping to get an options key boot screen with out having to prod the firmware, no joy there i guess lol,
its mainly my games machine, mojave is only there for updating/editing Martins OCLP config.plist when needed,
so i don't really need an options key boot screen, but it would have been nice to have it lol.
I have a 2018 Mac Mini for serious stuff like book keeping and so on.
was hoping i would not have to mess with the machine's firmware.
I'm running cMP5,1 with latest firmware 144.0.0.0.0, 6 core 3.46 Xeon, Radeon Vii, 64 gig 1333 mhz memory,
Mojave under Martin Lo’s OCLP config, machine runs great was just hoping to get an options key boot screen with out having to prod the firmware, no joy there i guess lol,
its mainly my games machine, mojave is only there for updating/editing Martins OCLP config.plist when needed,
so i don't really need an options key boot screen, but it would have been nice to have it lol.
I have a 2018 Mac Mini for serious stuff like book keeping and so on.
tsialex
Contributor
DIY Monkey
macrumors newbie
OK think I'll just leave things as they are.
Machine is running fine as is, don't want to risk it,
i have no use for an expensive door stop.
Machine is running fine as is, don't want to risk it,
i have no use for an expensive door stop.
Hello Mac Addicts!
Very interesting topic. I wish to create a new GPU firmware ROM to flash to my Sapphire RX580 E387 8GB video card to have Mac Boot screens for a Mac Pro 5,1! I want to modify my stock ROM and have tried to do it with the info on this post, and was able to get the commands to run, but it says there is not enough room in the rom. The readme says this usually happens on iMacs and not Mac Pro PCI cards. And that deleting the VGA support can free up some space. Anyone else deal with this on the RX580?
Here is my stock ROM if anyone wants to help me:
Very interesting topic. I wish to create a new GPU firmware ROM to flash to my Sapphire RX580 E387 8GB video card to have Mac Boot screens for a Mac Pro 5,1! I want to modify my stock ROM and have tried to do it with the info on this post, and was able to get the commands to run, but it says there is not enough room in the rom. The readme says this usually happens on iMacs and not Mac Pro PCI cards. And that deleting the VGA support can free up some space. Anyone else deal with this on the RX580?
Here is my stock ROM if anyone wants to help me:
Attachments
NC12
macrumors regular
You could try modifying your Mac Pros ROM instead if there isn’t enough space on your GPUHello Mac Addicts!
Very interesting topic. I wish to create a new GPU firmware ROM to flash to my Sapphire RX580 E387 8GB video card to have Mac Boot screens for a Mac Pro 5,1! I want to modify my stock ROM and have tried to do it with the info on this post, and was able to get the commands to run, but it says there is not enough room in the rom. The readme says this usually happens on iMacs and not Mac Pro PCI cards. And that deleting the VGA support can free up some space. Anyone else deal with this on the RX580?
Here is my stock ROM if anyone wants to help me:
Most Polaris cards like RX480/RX580/....have not enough empty code to inject the GOPEnabler.
If you're able to reflash a bricked card, you may try different roms, some rare can be found in techpowerup database with more room.
If you're able to reflash a bricked card, you may try different roms, some rare can be found in techpowerup database with more room.
Been doing a lot of research and did some BIOS ROM hacking and managed to get a RX580 semi working on my Mac Pro! Not sure if it's ok to do or not but I took a Nitro MAC EFI BIOS ROM from one of my cards that I bought on eBay that was Mac flashed for EFI screen, and noticed it uses the same memory as my normal RX580 card. Used Polaris Bios Editor to edit the rom to match my RX580 card and flashed it and it works. I get Mac boot screens, works perfect on the Mac. BUT my Win 7 won't load, hangs to black screen. Win 11 seems to work okay. Ideas?
Hi! I'm having a problem with my Mac 5,1
I have already enabled GOP, It works with my GTX 1050ti, but as that gpu is no longer supported I put a Rx 460 4GB Oem that I have, it works in mac OS but it works like GOP disabled, no boot menu or loading screen, only MacOS
I wish some help!
I have already enabled GOP, It works with my GTX 1050ti, but as that gpu is no longer supported I put a Rx 460 4GB Oem that I have, it works in mac OS but it works like GOP disabled, no boot menu or loading screen, only MacOS
I wish some help!
tsialex
Contributor
Did you re-flashed the factory GPU firmware? Follow this post:
EnableGop: Pre-OpenCore GOP support for EFI-era iMacs and Mac Pros
I very recently solved the same situation you seem to have: 5,1 bootROM with EnableGOP, OCLP, and a (used eBay) Sapphire Pulse RX 580 8GB with dual BIOS switch but no boot picker unless AMD Inject GOP was selected in the advanced OCLP config. There is a method for flashing GPU directly on a...
forums.macrumors.com
If even re-flashed the Apple native BootPicker does not work with the RX 460 OEM, then you have a GPU without GOP, extremely rare for a Polaris GPU, but happened with AMD 2xx and 3xx.
Yes! I did reflash it, because it was a rx 560D (not natively compatible with Mac OS) so I did a reflash and change it to an RX 460Did you re-flashed the factory GPU firmware? Follow this post:
EnableGop: Pre-OpenCore GOP support for EFI-era iMacs and Mac Pros
I very recently solved the same situation you seem to have: 5,1 bootROM with EnableGOP, OCLP, and a (used eBay) Sapphire Pulse RX 580 8GB with dual BIOS switch but no boot picker unless AMD Inject GOP was selected in the advanced OCLP config. There is a method for flashing GPU directly on a...
If even re-flashed the Apple native BootPicker does not work with the RX 460 OEM, then you have a GPU without GOP, extremely rare for a Polaris GPU, but happened with AMD 2xx and 3xx.
tsialex
Contributor
So, you most probably flashed a sligtly incompatible firmware, or a modified one, and then only macOS initializes it.
Maybe the reason is that I modified the TDP of the GPU Bios, because it was really high
tsialex
Contributor
Mac Pro EFI firmware only loads signed/valid OptionROMs, any modification makes the signing of the OROM incorrect, the OROM is invalid and rejected by the firmware.
Rejected OROM = no preboot configuration support via EnableGOP and only macOS drivers enable the GPU.
Same is valid for Windows SecureBoot, btw.
Do you recommend any Bios that can work with my GPU? I don't want to flash the stock ROM because is an rx 560D and it is not native for macOS
tsialex
Contributor
I have zero experience with RX 560D. I'd flash back the factory firmware and spoof a real RX 560 via OC, see OCLP instructions and posts about RX 6850 and other not recognized cards that require spoofing.