HackFlags 0x600 Registry Edit - AMD Radeon eGPU Boot Camp Error 12 Solution  

Tried everything all over again with 19041.264

No dice.  I'm done.  Feel so good having just wasted 8 hours on this project 😕 

@mackiewack, Only thing that worked is stay at 1903 and never update.  It's something broken in Windows and doubt it ever gets fixed.  No idea why.

@mackiewack, 2020 MacBook Air and Pro laptops need different set up procedures in Boot Camp. Take a look at our Build Guides then find a matching build to your equipment. The guide from @andygev35 is your best resource [build link].

Yes!  That was the help I was looking for.  I've read through the tutorial and it does appear to be different than what I've tried so far.  Looks like i'll just have to sink another hour or two into this!

SOLVED!!

It Just Works!!  I'm in shock.  Thank you @itsage and @andygev35.  The walk through was straight forward.  I have a couple of wrinkles to mention, but in short it just works!!  I'll mention those in a bit when I have a chance.

2020 Macbook Air with i5/8Gb Ram/512Gb SSD + Razer Core V2 + Radeon Vega 56.  Oh, and now I know that it has Samsung memory which has me thinking of flashing Vega 64 ROM...

Got force updated from the spring 2019 windows 10 build so didn't have much choice to try this out. Worked like a charm.

2019 13" TB MBP

Sapphire Vega 64

Mantiz Venus

Thanks for this hint! 

Quick Question: After applying this, does this enable you to be able to hot-plug any device in the other usb-c ports?  (Currently my system reboots if I put anything on the USB-C ports on the right side when the Core X is plugged in).

Could this still work together with apple_set_os enabled as well?

Respectively, can this registry key work as a replacement for disabling, for example, PCIe x16 in Device manager to solve error 12, but apple_set_os would still keep iGPU alive during boot.

What happens if eGPU is disabled, hot-unplugged with this regisrty key enabled? Does iGPU becomes alive?

HDMI would be plugged into iGPU in my case.

Posted by: @darkjz

Thanks for this hint! 

 

Quick Question: After applying this, does this enable you to be able to hot-plug any device in the other usb-c ports?  (Currently my system reboots if I put anything on the USB-C ports on the right side when the Core X is plugged in).

Just bit the bullet and tried for myself.  Happy to let you all know that applying the fix as stated on the Original Post works wonders! For the first time ever my MacBook Pro 2017 is able to have USB-C HotPlug of additional devices in the remaining 3 ports whilst using the eGPU Box.

Thanks for sharing this Registry Edit!!!

The registry entry does not really help to ‘improve’ anything on my MM 2018, 10.15.7 and Sonnet Puck 560 (internal HDMI connected). I mean, I am successfully
able to use the eGPU on W10 2004 wit all updates with set_apple_os and disabling PCIe x16 optionally for system stability (Othervise system freezes /restarts occur). However, when the registry entry is here:

1) With value 200 or 600 - the Radeon card is not able to boot anyway without the apple_set_os (disabled with ‘Z’). And when I boot it with it, error 12 is still there no matter if PCIe is enabled / disabled.

2) With value 400 - card can still boot with apple_set_os only but there is no error 12. However, the system is unstable with or without PCIe x16 disabled. Random freezes / restarts.

Anyway, the card is working great without the registry entry and with apple_set_os and x16 disabled.  I can boot / reboot / restart to macOS, hot-plug any other devices in USB-C ports. All is fine. Only on rare ocasions restarting from macOS to W10 leads to black screen and power off, but next time it boots fine again. And hot-plug does not work for eGPU in any case, but I do not really need it. Therefore, I see no benefit for me adding this registry entry for now.