MP 1,1-5,1 Mac Pro 5,1 Monetary with Opencore not Booting after windows 10 legacy install

[petedv]

Hi Guys, I'm pretty new to this so apologies for my ignorance.
I want to thank all those contributors on here, who have helped me so far.

My son had been pestering me for a "basic" gaming pc -

I had a 5,1 cMP at home so I'm trying to revive it for him.
I purchased a radeon 5700 xt and got the machine successfully into Mojave using dosdude followed by an upgrade straight to monetary. WIFI did not work as expected.

Following this I decided to install windows 10 legacy mode, via burned dvd on a separate ssd plugged into one of my slots.
I'm using a really old copy (maybe this is the problem, possibly 1507,) ran brigader (unsure if I ran correctly) however since the install I can't boot back into monetary again, via the boot picker, just the white screen with the apple logo stuck half way.
Have I not installed open-core correctly ?

Another problem I have is that I cannot seem to get windows to update, to the 22h2 version - thus leaving me with a black screen on windows boot following required updates - therefore I cannot update the drivers for the graphic card is that correct ?
When I do the updates I'm presented with a black screen on boot for windows, - btw I'm just booting windows by holding alt/option on startup.

The question I have for all you guys is that would I be better to start over with a fresh install ?
and following that go with a windows 11 copy ? any help would be much appreciated.

 

[h9826790]

Sorry, I am very confused.

You installed a non flashed 5700XT, then hold option key to boot? This shouldn't work. Your cMP should hang with black screen before you select Windows from the non-exist boot screen.

Graphic card driver is independent to Windows update. You should go to the AMD website to download the latest driver for 5700XT, but not via Windows update.

Dosdude Mojave then update straight to Monterey? The 5,1 can install and run Mojave natively, no need to use Dosdude patcher. And even that's patched, I don't think you can further upgrade to Monterey. Even it allow you to install, during OS upgrade, all system files will be unpatched, which means your cMP won't able to boot Monterey just like that.

You haven't mentioned how you installed OpenCore, and what the config is, we can tell if you install OC correctly.

 

[petedv]

Sorry apologies the card was flashed, and with the version of windows I'm running I can't use the AMD software to get the card running. As for the version of opencore I followed the guide as per macprovid cards Europe which can be found here

Installing macOS Monterey 12 on unsupported Mac Pro

See how to install macOS Monterey 12 on unsupported Mac Pro.

www.macvidcards.eu

I had no problems booting in a fully functional monetary before before installing windows to the second ssd.

 

[h9826790]

Ok, I get a better picture now.

If that's a flashed card, you are very safe to perform the 4x NVRAM reset (and please do a SMC reset as well).

Since nothing changed inside Monterey, and nothing changed in OC. Then very likely either somehow Windows corrupted the macOS partition (very low chance). Or something in the NVRAM now prevent macOS to boot properly.

 

[h9826790]

I am not sure what's wrong in your Windows. download and install AMD software should be very very straight forward.

 

[petedv]

Thanks I'll give that a try

 

[petedv]

after nvram reset & sec now in a constant boot loop apple logo, no option key working, I think I need a fresh install

 

[petedv]

after nvram reset & sec now in a constant boot loop apple logo, no option key working, I think I need a fresh install

"smc"

 

[h9826790]

after nvram reset & sec now in a constant boot loop apple logo, no option key working, I think I need a fresh install

Holding option key (wired keyboard) should work with your flashed card.

If you have Windows, Monterey, OpenCore on three different partitions (and most likely on more than one hard drive), at least one of them should show up on the Apple startup manager.

The only exception I know is when you have a Sonnet TempoSSD installed. Then the Startup manager may not work, and all you get will be a light grey screen (but not black screen).

 

[tsialex]

Are you sure that your RX 5700XT is flashed with MacEFI? Did you had a working native BootPicker previously?

You will probably need a BootROM reconstruction service. Seems you got a very corrupted NVRAM.

When the NVRAM volume itself is corrupted and everything else inside the BootROM still works, if you remove the RTC battery, remove all disks from the Mac Pro and only install disk with a supported macOS release, you still can boot.

Even when you have a Windows boot coup that only allows your Mac Pro to boot Windows - resetting the NVRAM won't work for this case - removing the RTC battery completely bypass the NVRAM, so you'll need to install a disk with a fully supported macOS release to boot again. Somethings won't work correctly without the RTC battery, like clock and Wi-Fi, but it's enough to get you started.

It will be easier to go back to a somewhat working state if you have an AppleOEM GPU or even a PC GPU that works with Mojave like a RX 580, VEGA/VII. RX 5700XT requires Catalina. With an AppleOEM GPU, install anything from Mavericks to High Sierra, except Yosemite.

 

[h9826790]

Are you sure that your RX 5700XT is flashed with MacEFI? Did you had a working native BootPicker previously?

You will probably need a BootROM reconstruction service. Seems you got a very corrupted NVRAM.

When the NVRAM volume itself is corrupted and everything else inside the BootROM still works, if you remove the RTC battery, remove all disks from the Mac Pro and only install disk with a supported macOS release, you still can boot.

Even when you have a Windows boot coup that only allows your Mac Pro to boot Windows - resetting the NVRAM won't work for this case - removing the RTC battery completely bypass the NVRAM, so you'll need to install a disk with a fully supported macOS release to boot again. Somethings won't work correctly without the RTC battery, like clock and Wi-Fi, but it's enough to get you started.

It will be easier to go back to a somewhat working state if you have an AppleOEM GPU or even a PC GPU that works with Mojave like a RX 580, VEGA/VII. RX 5700XT requires Catalina. With an AppleOEM GPU, install anything from Mavericks to High Sierra, except Yosemite.

If I read OP's message correctly. I think he want to say he bought his card from MVC EU. Which should be a genuine flashed card.

And it seems he followed that MVC EU's page to install Monterey, which need to hold Option key to select the USB installer. Therefore, most likely his card is flashed.

However, may be as you said, the NVRAM is very corrupted.