2015 27" iMac 5K (R9 M390) [6th,4C] + RX 580 @ 16Gbps-TB2>TB3 (Gigabyte Gaming B...
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[Solved] 2015 27" iMac 5K (R9 M390) [6th,4C] + RX 580 @ 16Gbps-TB2>TB3 (Gigabyte Gaming Box) + Win10 [abelviking]  


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Joined: 3 years ago

Topic title
iMAC Late2015 27 inch 5K dGPU: RADEON 9 M390 + AORUS Gaming Box RX580-TB2 + Win10 - build 17134.rs4_release.180410-1804 - codename 1803 + [abelviking]


System specs
iMAC 5K 27 - BIOS version:Apple Inc. 25/09/2018
dGPU M390
OSX 10.12.6 - not used
Windows 10 version 1803 running Windows To Go over USB 3 in UEFI mode.
BootcampDrivers.com Adrenaline 19.3.1

Notice: Ai
AIDA64 throws a memory Access error when starting the GPGPU benchmark so I don't know if I need the HD2 firmware switch to make things go faster.



eGPU hardware 

eGPU software
bootcampdrivers.com. Do not use anything else. Build Version:
Adrenaline 19.3.1


Hardware pictures 
Now that I figured things up they'll be coming up.



Speculation: Since the iMAC is running OSX 10.12.6 its BIOS has been updated to 2018 version. That in combination with the 1803 of windows might be the reason I didn't have to DSDT my device.
Installation steps

  1. Boot into Safe MODE.
  2. DDU your AMD GPU
  3. Boot into regular mode
  4. Install bootcampdrivers.com, specifically Adrenaline 19.3.1
  5. Hot plug the Gaming Box
  6. Go to Device Manager and find the RX580 with Code 12 error.
  7. Uninstall the RX580 from Device manager and leave drivers behind.
  8.  Reboot.

Repeat steps 7 and 8 every time you want to use Internal screen otherwise just boot up the computer with the Aorus Gaming box COLD plugged.

Please IGNORE the rest of this post if you want to do is get your setup up and running. If you want to find out I was having similar problems to you then by all means, read on. I rather keep all my findings linked to my build so people can find out how I arrived to it.

I had a total of 5 DIFFERENT installation attempts. I'll leave the most relevant here for history purposes. If you want to see more, go here.

egpu.io attempt 2 with bootcampdrivers.com:
Adrenaline 19.3.1 were installed after a DDU 
hot plug the Aorus Gaming box, it goes into Code 12 error.
Reboot the system
Both video cards are recognized and internal screen is turned completely off, FINALLY.
Still wondering if I can get to use the internal screen.
Video game resolution switching turns both screens off, something is iffy with this configuration.
Some problems with FAN RPM and LED lights not coming up. At a certain point the video game was running in full screen and the eGPU fan was off.

eGPU.io approach - official drivers:
Safe Boot in Offline Mode.
DDU the OS 
Install latest AMD drivers for MAC as per guide: https://support.apple.com/en-us/HT208908
Hot Plug the Card.
Screen goes blank
Switch iMAC off/on with the eGPU plugged in.
dGPU goes into Code 43 error and internal screen REMAINS on, IMPORTANT: No video data goes to it, but the LEDS are on!
AMD XConnect comes online and HDMI output works.

1.- The drivers listed for the RX580 are from 2017. The drivers I installed for the M390 are from 2018.
2.- The firmware doesn't seem to be "turning off the screen because two video cards are connected in a non OSX environment" but simply the M390 is failing to boot up with error Code 43, as described here: https://egpu.io/forums/expresscard-mpcie-m-2-adapters/mpcieecngff-m2-resolving-detection-bootup-and-stability-problems/paged/11/#post-56881
Falling into section: 2.III -  error 43: running a NVidia dGPU and eGPU 
but with AMD.
3.-Once I get things working with the eGPU things get more fun. Turning the system off and unpluging the eGPU renders the system unusable. One must boot up with the eGPU and go into Safe mode to uninstall the drivers. This seems like a driver issue rather than Apple's firmware turning off the screen.

Insight: On this approach I used the official AMD+APPLE drivers from amd.com. These drivers do NOT detect the eGPU, that is the same behavior with the OSX downloaded AMD+apple drivers for Bootcamp. Instead the computer must be connected to the Internet to download the RX580 drivers and install AMD XConnect. That explains the Code43 error on the dGPU M390 because of driver conflicts.

By myself - with computer connected to internet:
Install Bootcamp drivers from Apple downloaded with Bootcamp Manager in OSX.
Hot Plug the eGPU - black screen of uselesness.
Turn Off/ON 
External Screen works.

Newbie approach 2 - Code 12 on eGPU
Force driver installation by using the HAVE DISK Windows 95 feature under safe mode with HOt plugged eGPU to use the REGULAR AMD drivers instead of the ones marked for Apple Mac.




Comments So this Setup is AMD on AMD with the exact same behavior between the eGPU and the BIOS/OS as this user posted with his laptop, even though I have an iMAC(a glorified laptop) with TB 2.: https://egpu.io/forums/builds/2018-15-macbook-pro-rp560x-rx580tb3-gigabyte-gaming-box-macos-win10-buffaloseven/#post-56873
1: Hot plug gets the drivers installed but doesn't get the eGPU to output video.
2: Cold boot AFTER hot plug gets the eGPU to output video and the dGPU to go into code 43 until the drivers are re-installed, what a mystery.
3: In order for drivers to work one must HOT plug the Card, then switch system Off/On.

What doesn't work:
1.-The iMAC screen DOES NOT turn off...the back light is still on killing my IPS.
2.-The dGPU goes into Code 43 error and it WON'T come back up unless I log into Safe Mode and do a driver re-install. It doesn't like the eGPU drivers.


This topic was modified 3 years ago

Sytem InfoiMAC Late 2015. dGPU AMD M390, OSX 10.12.6, Windows 17134.rs4_release.180410-1804(1803). GYGABYTE AORUS RX580 miniITX eGPU my signature

2015 27" iMac 5K (R9 M390) [6th,4C] + RX 580 @ 16Gbps-TB2>TB3 (Gigabyte Gaming Box) + Win10 [build link]