late-2015 27" iMac 5k M390 + [email protected] (AORUS Gaming Box via TB3->TB2 adapter) + Win10 [PraVaLoRiuS]  


Active Member
Joined: 7 months ago
Posts: 5
June 4, 2018 3:42 pm  

System specs  

MODEL:    iMac 5k 27in Late 2015 
CPU:           i5 6500 @3.2
RAM:          16gb DDR3 1600
iGPU:         This model doesn't have or use one 
dGPU:        Radeon R9 M390 2gb
OS:              Bootcamp Windows 10 pro (I haven't done this on Mac osx simply because i do not need that much power there)


eGPU hardware 

eGPU:   Aorus gaming box 1080 8gb  (
Firmware Stock (i haven't done in on my MBP2017 that has TB3 and is pretty much Plug and play, auto install script etc)
TB3 to TB2 original Apple adapter
HDMI to HDMI cable
Samsung 24in curved  (

Hardware pictures 

I'll post some later when the mess is done


Installation steps 

I'll try to not to add all the steps i did without positive results, they are SOOOO many that are hard to remember.
After install Bootcamp for 3rd time (mostly because  of previous failures and BSOD, and PlugNrestart kind of things)
So this iMac model does not boot with the eGPU connected, so you CANT just restart without wait until is off to unplug it and wait for the Windows dot circles to Hot plug it (You can plug it running windows, is better you can get used to do it like this)

At this stage your Windows will detect it and install drivers, and after this you will get the CODE 12 on Device Manager. 

I followed many guides from this site and other, but the best one was this one from top until OPTION 1 that was far out of my league of knowledge.  
and with the help and guidance of @nando4 that fix and did all the dirty job with my DSDT files, i was able to screw his work and make my computer to hang every time I plug my eGPU on any stage of booting or windows. (you can easily solve this with the Unload file provide with the files that Nando4 gave me)

Again after re read his guide, i discovered that i wasn't able to copy the dsdt file to CLOVER under windows, it was far too complicated for my skill level and at this point i decide to follow this other guide from @Mikeal
and follow it from step 4 to victory. (that is pretty much just install Clover and copy your DSDT to it but under windows i wasn't able to achieve it, is far easier to do it under OSX)
Now every time i need to boot from USB stick with Clover with my eGPU unplugged and plug it when i see windows dot circles moving.

All the outgoing of my eGPU is showing up on my external monitor since as far as i know in this iMac model its impossible to do it with the 5k 27in screen.

I had my system restarted several times to test it, and the only time my eGPU got disconnected and not working (windows was fully functional with the dGPU) was when i put it to sleep and it was back after a restart and hot plug when dot circles appeared.



CUDA-Z Report
Core Information
Name: GeForce GTX 1080
Compute Capability: 6.1
Clock Rate: 1733.5 MHz
PCI Location: 0:61:0
Multiprocessors: 20
Threads Per Multiproc.: 2048
Warp Size: 32
Regs Per Block: 65536
Threads Per Block: 1024
Threads Dimensions: 1024 x 1024 x 64
Grid Dimensions: 2147483647 x 65535 x 65535
Watchdog Enabled: Yes
Integrated GPU: No
Concurrent Kernels: Yes
Compute Mode: Default
Stream Priorities: Yes

Performance Information
Memory Copy
Host Pinned to Device: 1248.48 MiB/s
Host Pageable to Device: 1078.88 MiB/s
Device to Host Pinned: 1317.04 MiB/s
Device to Host Pageable: 1136.58 MiB/s
Device to Device: 102.666 GiB/s
GPU Core Performance
Single-precision Float: 9222.3 Gflop/s
Double-precision Float: 303.228 Gflop/s
64-bit Integer: 695.204 Giop/s
32-bit Integer: 3165.03 Giop/s
24-bit Integer: 2374.49 Giop/s

Generated: Mon Jun 04 14:49:47 2018




I play PUBG a lot, and is a heavy game to process, my old configuration was 1920x1080 Very low graphics with medium Anti aliasing  with 50 to 60 fragile FPS that used to go to 20 on populated areas or smoke grenades.
Now even with a TB3 eGPU working in a experimental fix under bootcamp in a TB2 iMac, i must say that the result are impressive, i'm amazed with my new eGPU.] The same game, 1920x1080 on ULTRA settings and maximum field of view, is running at 90 FPS AVG with fewer to no drops. Outstanding.
I cant wait to try some more.

My workflow is just light CPU use, i can do it in my old MBP 2012 with no issues so gaming is the most benefit of this upgrade.

Soon I will add my system & eGPU details or a build link to this my signature to give context to my posts

Mech314, mrgeque and nando4 liked
Eminent Member
Joined: 1 year ago
Posts: 20
June 23, 2018 7:43 am  

are you ONLY powering external monitor using egpu? Have you tried accelerating the internal monitor? only reason I ask, if you have 2gb of dGpu memory and 8gb of of eGpu memory I THINK youll see an increase in frames per

Soon I will add my system & eGPU details or a build link to this my signature to give context to my posts

Active Member
Joined: 6 months ago
Posts: 10
July 8, 2018 6:08 pm  

Hey man! Thank you for this guide!

I have a question.
Does the internal screen work? I understand that it is not powered by eGPU, but does it work when eGPU is active?
Both in bootcamp and macOS?

Soon I will add my system & eGPU details or a build link to this my signature to give context to my posts

New Member
Joined: 5 months ago
Posts: 1
July 12, 2018 3:11 pm  

Hi Guys,

I'm digging through this site and I'm a little overwhelmed and I'm hoping someone here has gotten this to work.

I do a lot of C4D work and my team and I are looking for a solution to run our machines for C4D Redshift and Octane rendering... So we need Nvidia cards that have plenty of cuda cores.
Will any of these cards work with an eCPU on our computers? What would you recommend?
I’m running a:
iMac (Retina 5K, 27-inch, Late 2015)
4 GHz Intel Core i7
AMD Radeon R9 M395X 4096 MB


Soon I will add my system & eGPU details or a build link to this my signature to give context to my posts

Active Member
Joined: 7 months ago
Posts: 10
July 12, 2018 5:07 pm  

Hey Bluenote, I'm running the same iMac as you and I've gotten things working by using the guide below… It seems there are a couple of new methods now, but I'm in a similar boat to you, just trying to gather some info…

My setup is a sonnet breakaway 550w with 1080ti. Like yourself, I'm using it for Redshift and C4D… So no monitor whatsoever connected to the egpu… Been great so far.

Soon I will add my system & eGPU details or a build link to this my signature to give context to my posts

New Member
Joined: 2 months ago
Posts: 1
October 14, 2018 5:34 pm  

Hey Benek,

I also have the same setup. Glad to know you got the internal screen working! Is it for windows only or does it work in MacOS also?

Soon I will add my system & eGPU details or a build link to this my signature to give context to my posts