2013 Mac Pro (FP D500 x2) [3rd,12C,E] + RP 580 @ 16Gbps-TB2>TB3 (Blackmagic eGPU) + macOS 10.14.6 & Win10 1903  

Good Day Everyone..

After spending weeks on this problem I have found a solution.

I just want to post an Update on this issue.

I managed to get this to work on Both PC and MAC.

Here are my Specs:

Macpro Late 2013 128GB

OS:

• Mac: OSX Mojave 14.6
• Pc: Windows 1903

Graphic Cards

• AMD Firepro D500 (FireGL V)
• Blackmagic Pro EGPU Radeon Pro 580 8Gb
• Razer core X RX480

Displays:

• 32" BENQ EW327OU
• LG HDR 4K
• Wacom Cintiq 13 HD

This is how I did it.

I connected the Blackmagic Egpu into to the Mac using a genuine Thunderbolt 2 to USB -C Adapter

I downloaded Purge Wranger.

GitHub - mayankk2308/purge-wrangler: AMD & NVIDIA eGPUs for all Thunderbolt Macs.

I ran TERMINAL and I installed Purge Wrangler. I selected AMD as the driver and followed the installation procedures.

After that I restarted the computer and connected the Blackmagic egpu to the bottom-right port of the thunderbolt 2 port and it worked perfectly with the Mac.

With Windows.

After trying different types of windows version and trying different approaches with DSDT etc, none of it worked.

So I downloaded the 1903 Windows version OS build 18362.30. I installed windows using bootcamp.

https://archive.org/details/windows-10-1903-x-64

When setting up windows its important for you to participate in the Windows insider Preview. This is really important for this to work.

It took some time (10-15mins) for Insider to complete installation.

After installation of windows, I download bootcampdrivers.

BootCampDrivers.com: Turbo-charged AMD graphics drivers for Mac BootCamp users.

The driver that worked for me was the NOV 2019 Blue edition.

After following the installation procedures in Safe Mode, I restarted using the computer  into PC and installed the Bootcamp drivers Nov 2019 Blue Drivers.

I encountered and Error 12. The EGPU was not even recognised.

So I went to the device manager and I disabled the following PCL-to-PCL Bridges:

Pictures below.

After disabling the PCL bridges, I went to the Windows Insider Program. This would not work without receiving updates 

I restarted and Voila. It worked.

I connected all my devices including the Wacom CINTIQ13HD, OCULUS CV1, ETC and it all worked perfectly.

I ran Radeon Pro Setting and the picture is displayed below.

However, I noticed that the windows only recognised one of the AMD FIREPRO D500 card.

I hope this helps anyone facing the same issues with the same device.