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iM 4,1-14,4 EnableGop: Pre-OpenCore GOP support for EFI-era iMacs and Mac Pros
- Thread starter Bmju
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Some RX 560 models are known for weird colors at pre-boot configuration with HDMI connected displays and a pink tint while running macOS, test with DisplayPort to see if the same behavior happens.
Also, check TechPowerUp to see if your GPU have firmware updates.
Thank you, i will check and report later!
@tsialex thank you very much! Via displayport everything is just fine! Never thought that hdmi could be the problem here
2nd edit
Doesnt work on a 4k display, but works on a full hd display. No problem.
In a few weeks i will upgrade to rx6600
@tsialex thank you very much! Via displayport everything is just fine! Never thought that hdmi could be the problem here
2nd edit
Doesnt work on a 4k display, but works on a full hd display. No problem.
In a few weeks i will upgrade to rx6600
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Please post the maker and model of your RX 560, so people will find it when searching for similar issues. Even better if you could take a photo of the label with PN/SKU/firmware version.
I have a Sapphire RX 550 (Baffin core) originally with this vBIOS 113-367BF-U22 which works fine on macOS, but I haven't had success modifying its firmware to include EnableGop. Following these steps, I was able to:
1. update its GOP from 1.65 to 1.69, which it's running currently (attached)
2. split the file in half to avoid modifying its 2nd half
3. delete the VGA block and run atomdis before and after fixing the size values and table addresses (including the hidden one at 0x22 that wasn't listed)
4. recombine the modified 1st half with the original 2nd half
5. use ATOMTableResize to update the checksum (also attached)
But, this vBIOS wouldn't show a picture when installed on my cMP3,1, and when in my Windows 10 PC its Device Manager listed the card but didn't recognize it as anything more than a basic display adapter and wouldn't show a picture either. (Naturally, it also wouldn't work with the vBIOSes generated by running vBiosInsert.sh to insert EnableGop or EnableGopDirect v1.4 either.) Did I miss something, or is this card not compatible with the above process?
1. update its GOP from 1.65 to 1.69, which it's running currently (attached)
2. split the file in half to avoid modifying its 2nd half
3. delete the VGA block and run atomdis before and after fixing the size values and table addresses (including the hidden one at 0x22 that wasn't listed)
4. recombine the modified 1st half with the original 2nd half
5. use ATOMTableResize to update the checksum (also attached)
But, this vBIOS wouldn't show a picture when installed on my cMP3,1, and when in my Windows 10 PC its Device Manager listed the card but didn't recognize it as anything more than a basic display adapter and wouldn't show a picture either. (Naturally, it also wouldn't work with the vBIOSes generated by running vBiosInsert.sh to insert EnableGop or EnableGopDirect v1.4 either.) Did I miss something, or is this card not compatible with the above process?
Yes, you missed the most important point - EnableGop is not compatible with early-2008 Mac Pro or PCs…
With stripped VGA driver you should get display output in a PC in UEFI startup mode (with OS with full UEFI support like Windows 8 and above, which do not need the VGA driver until OS is loaded) in correct resolution.
I'm not 100% sure, but it might work also with legacy boot, if the driver for videocard is installed before exchanging card/flashing VGA-less bios. But it will lack video output until OS is loaded and recovery environment not working.
If there exists a smaller GOP for your card or earlier, smaller version of EnableGOP: Better opt for it instead of removing VGA-part. But yes, it won't make it compatible to MP3.1, too.
I'm not 100% sure, but it might work also with legacy boot, if the driver for videocard is installed before exchanging card/flashing VGA-less bios. But it will lack video output until OS is loaded and recovery environment not working.
If there exists a smaller GOP for your card or earlier, smaller version of EnableGOP: Better opt for it instead of removing VGA-part. But yes, it won't make it compatible to MP3.1, too.
Mod with this vBIOS 113-367BF-U22 file,added EnableGOP,100% work with 2009-2012 Mac Pro,and your's rom GOP1.69 also added EnableGOP
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Thanks all for the feedback: tsialex for clarifying that EnableGop won't work for the cMP3,1 whether installed in either the Mac or GPU firmware (which the original post doesn't explicitly state), Borowski for confirming it should work and suggesting the use of an older version, and jeanlion for posting their own modified firmware files. I've since patched in EnableGop 1.1 which fits in the RX550 vBIOS without having to remove the VGA section. It still works on my cMP3,1 for macOS and Windows (BIOS mode) as long as one doesn't hold Option during boot, and also works in my EFI-based PC. If I find a compatible Pro to test it in I'll update this post.
hey all, this is amazing work here! i'm new to mac modding but have been using hackintoshes for some time.
the instructions are a bit unclear on github. do i first dump my mac rom with rom dumper, pack in enablegop 1.4 ffs from github to make a custom rom, then flash it back with rom dumper? thanks
the instructions are a bit unclear on github. do i first dump my mac rom with rom dumper, pack in enablegop 1.4 ffs from github to make a custom rom, then flash it back with rom dumper? thanks
Thats basically it. Lance made a very detailed video:
Great video indeed, and thanks for your ROMtool / dedication to the Mac Pro community.
Can this tutorial be used for a Mac Pro 5,1 using OCLP 0.6.8 and macOS Ventura? I'm on the edge flashing my Mac Pro 5.1 (mid-2012) with a currently installed a Mac EFI flashed EVGA GTX-680 4GB FTW upgrading to a Sapphire Pulse RX 580 8GB. I'm a bit confused by the Open Core (OC) and Open Core Legacy Patcher (OCLP) what I use.
Thanks in advance.
The reconstructed ROM service from @tsialex offers since some time ago 3 different ROMS, with 3 different GOP options. I was so happy when I saw again the boot screen on my Macs Pro with unsupported GPUs.
You can use it with OC, with OCLP and without them. If you have a supported OS (High Sierra, Mojave) available, then use this to read and write the firmware. If you use High Sierra, pull the other drives temporarily not to run into the Preboot issue (https://github.com/Macschrauber/Macschrauber-s-Rom-Dump/blob/main/Rename_and_repair_preboot.md)
Would this have anything to do or help with corrupt display (display splitting into four, whiteish) on Win10 when installing proprietary AMD drivers? (ATI 4670, iMac 10,1). External monitor connected via mini-DP works like a charm. Built in monitor is messed up.
Not even a supported GOP GPU, will do nothing.
EnableGop is just to provide pre-boot configuration support with modern GPUs, nothing to do with Windows after it is loaded.
Thank you for your swift reply. Downloaded the required files and made a backup of the Mac Pro 5,1 bootrom. May I ask you or @tsialex - like Lance mentioned in his video - to have a look at my rom backup .bin file as a final safety measurement before creating the new rom and flashing it into the bootrom? There are a few things that differ from the output Lance showed in his tutorial. Thanks in advance.
Thanks for your reply, now I get it. Can you think of any solution or what's causing my problem? I dual boot Ventura and UEFI W10 with Opencore. When using MS Basic Display Adapter, the built in monitor works as it should, but no external monitor output. If I install AMD drivers, then the built in monitor is corrupted but I do have output externally.
This is a driver issue, you should try the Apple BootCamp drivers to see if the issue can be resolved. People with the same iMac maybe have a workaround, search/post on the iMac forum.
Hello all,
After a botched update of Martin Lo's OC package, my 5,1 wouldn't boot Mac anymore. Somehow managed to boot into Windows (10) for some time trying to fix opencore (was able to fix a typo in the plist) but then at some point who ld stop booting altogether (no more bootpicker on my 6800xt).
Today, found my gt120 card again and installed Mojave onto a new ssd (now opencore install yet). Then used @Macschrauber's RomDump tool to be greeted with this:
Invalid VSS Store 1 header (serious issue!)
Idea is to perform enableGoP and then switch back to my original SSD (with OC) + rx6800xt. (And rebless opencore as I I understand?)
What are my options?
Thanks to anyone that can help!
Cheers,
Ingo.
After a botched update of Martin Lo's OC package, my 5,1 wouldn't boot Mac anymore. Somehow managed to boot into Windows (10) for some time trying to fix opencore (was able to fix a typo in the plist) but then at some point who ld stop booting altogether (no more bootpicker on my 6800xt).
Today, found my gt120 card again and installed Mojave onto a new ssd (now opencore install yet). Then used @Macschrauber's RomDump tool to be greeted with this:
Invalid VSS Store 1 header (serious issue!)
Idea is to perform enableGoP and then switch back to my original SSD (with OC) + rx6800xt. (And rebless opencore as I I understand?)
What are my options?
Thanks to anyone that can help!
Cheers,
Ingo.
When you have a Windows boot coup and you can't boot macOS after a NVRAM reset, your NVRAM volume is corrupted (you already know that) and is probably read-only already. You gonna need the BootROM reconstruction service.