MP 1,1-5,1 RX580 won't show anything when trying to restart into MacOS

[Peet_B]

I wanted to install windows, and did it the simple way by taking the SSD out of my windows machine, and plugging it into my Mac Pro 5,1. The first time, I used the original HD5770 and everything booted just fine. I went ahead and installed the bootcamp ánd AMD drivers, so my RX580 could be used with bootcamp.

Though I did all of this, my RX580 shows no sign of life when wanting to boot into Windows. And when I try to boot back into MacOS by resetting the PRAM, it doesn't show anything either. The only solution there is now, is to throw in my HD5770, choose MacOS as the startup disk, and reinstall the RX580. Doesn't seem quite right to me does it?

The only things I can think of is that I have pulled a SSD straight out of a windows machine, but that doesn't declare why my RX580 won't work, even after resetting the PRAM.
The other thing is that my MacOS is installed on an NvME drive, although that doesn't make sense either...

I'm a bit lost now. What is your guys best thoughts on this?

 

[MIKX]

Boot into Recovery : Command + R then select Startup Disk.

 

[Peet_B]

The problem is it won’t even boot into recovery mode. (Technically it does but I can’t see anything). It looks as though the RX580 stops working after I hold the option key on startup to select the disk. After that when I change GPU’s and boot back into OS X it shows that no drive is selected for boot...

UPDATE: I reinstalled the HD5770, and even there recovery didn't load, it just loaded right into windows. The ONLY thing that works is holding the ALT key and selecting MacOS. Though the weird thing is that that only works with the HD5770, if I do the same key sequence but with the RX580 installed it still shows black screen. And on top of that, when I finally boot back into MacOS, I see there is NO startup disk selected, I just don't get it...

 

[DearthnVader]

The problem is it won’t even boot into recovery mode. (Technically it does but I can’t see anything). It looks as though the RX580 stops working after I hold the option key on startup to select the disk. After that when I change GPU’s and boot back into OS X it shows that no drive is selected for boot...

UPDATE: I reinstalled the HD5770, and even there recovery didn't load, it just loaded right into windows. The ONLY thing that works is holding the ALT key and selecting MacOS. Though the weird thing is that that only works with the HD5770, if I do the same key sequence but with the RX580 installed it still shows black screen. And on top of that, when I finally boot back into MacOS, I see there is NO startup disk selected, I just don't get it...

Alt-booting doesn't change the Startup Disc in NVRAM, only the Startup disk control panel or the bless command does.

 

[Peet_B]

Alt-booting doesn't change the Startup Disc in NVRAM, only the Startup disk control panel or the bless command does.

Yeah I know, but the point is that when I choose to boot into MacOS, it simply doesn't do that... I have to plug in the HD5770 to just see anything. The weirdest thing is that I couldn't even boot into recovery mode. I unplugged the Windows drive and I'm attempting a clean install on a different drive now.

 

[DearthnVader]

Yeah I know, but the point is that when I choose to boot into MacOS, it simply doesn't do that... I have to plug in the HD5770 to just see anything. The weirdest thing is that I couldn't even boot into recovery mode. I unplugged the Windows drive and I'm attempting a clean install on a different drive now.

So, even when you selected the macOS boot drive in the startup disk control panel, it won't reboot to the macOS?

 

[drsoong]

It looks as though the RX580 stops working after I hold the option key on startup to select the disk.

UPDATE: [...] if I do the same key sequence but with the RX580 installed it still shows black screen. And on top of that, when I finally boot back into MacOS, I see there is NO startup disk selected, I just don't get it...

The RX580 isn't supported during the boot sequence of macOS. Only the full drivers loaded, when the OS itself loads the desktop, are supported.

Anything requiring access before that, yields only a black screen, and makes selecting recovery mode, or choosing to boot into Windows/macOS impossible.

That is also a reason to keep the old HD5770, when installing a RX580 for performance reasons.

Although, there is a thread here on Macrumors on patching and flashing the Bootrom of the RX580 card - apparantly leading to some success -, this is some serious tinkering. Certainly not recommended for the faint of heart...

... or people who didn't even read up on the drawbacks of installing a RX580 in their MacPro.


On the issue on forcing booting in the respectively "other" OS, i.e. "macOS -> Windows" and "Windows -> macOS", there might be a solution. As I am not using Bootcamp, I don't know anything about that.

-drsoong