2019 16" MacBook Pro (RP5500M) [9th,8C,H] + RX 5700 XT @32Gbps-TB3 (Sonnet Break...

2019 16" MacBook Pro (RP5500M) [9th,8C,H] + RX 5700 XT @32Gbps-TB3 (Sonnet Breakaway 650) + macOS 10.15.3 & Win10 1903  


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Joined: 2 years ago

Hi all

Wanted to share my success after reading a lot of 16" guides but with no success getting ERROR 12 and eventually got it working. There are some very specific things not explain in other posts that I will explain in mine. I have retested it by formatting Bootcamp and redoing all of it for science 🧬 . (worked first time)

System specs (model inc screen size, CPU, iGPU, dGPU, operating system which eGPU is being used)

MacBook Pro (16-inch, 2019)

  • CPU: 2.4 GHz 8-Core Intel Core i9
  • MEM: 64 GB 2667 MHz DDR4
  • HDD: 2TB SSD
  • dGPU: Radeon 5500M
  • eGPU:Radeon RX 5700 XT 8 GB


eGPU hardware (eGPU enclosure, video card, any third-party TB3 cable, any custom mods)

Sonnet BreakAway 350 - upgraded PSU to 650W


Installation steps (what did you do to get it all going?)

MacOS is plug in and play so skipping this.. 

I would suggest downloading all the guide files below before you start on a USB and installing or copying the files from it. 

Installing Windows + eGPU:

  1. Install Windows 10 1903 V1 in bootcamp
  2. Start windows with no internet
  3. Install Mac Bootcamp drivers 
  4. Run DDU from latest bootcampdrivers.com - Restart
  5. Install latest bootcampdrivers.com- Restart
  6. Install Windows Update 1903 (.295) - Windows will restart a few times
  7. Disable Windows update in services.msc - Restart - reconnect internet
  8. Boot in Mac OS and install bootx64.efi
  9. Do the Port Dance in the following order - the TIMING on the dance messed me about until I got it down pat (Left and Right is distinguished by looking at the laptop screen)
    1. Leave eGPU plugged in TOP LEFT T3 port on power on (Don't think it matters if you plug it in at efi loader, but this worked for me)
    2. Press enter when bootx64 efi loader has detected your eGPU and is counting down
    3. WAIT until Windows Logo shows up AND ... I SAY AND The Windows loading circle has made one rotation...
    4. THEN and only THEN plug it out and move it to the TOP RIGHT side and wait.. 
    5. Wait until Windows is loaded, you can see your back ground, I looked in computer manager and saw the ERROR 12
    6. THEN I moved the eGPU to the ORIGINAL PORT on LEFT side again
    7. Windows freaks out does a few chimes and BAMMM.. your screen flickers get it's brackets and you have the eGPU working

For those who cares, my internal screen stays on and working, I did manage to turn my brightness down and thought the internal screen stopped working, didn't care as long as the dGPU was working, but it was the brightness.

NOTE: If your eGPU stops working or shutdown, mine started over heating inside the enclosure since I upgraded my Macbook Pro from 2018 to 16", just opened the enclosure to get unrestricted air and it calmed down and stopped shutting down. Don't know what the 16" is doing to the eGPU that the board heats up more. 


Benchmarks are on the Bootcamp side Roll

Will do a proper Mac and Bootcamp Benchmarks and update


This topic was modified 3 days ago

Pending: Add my system information and expected eGPU configuration to my signature to give context to my posts

jangoloti liked