2017 27" iMac 5K (RP575) [7th,4C,K] + RX 5700 XT @32Gbps-TB3 (Razer Core X) + ma...
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2017 27" iMac 5K (RP575) [7th,4C,K] + RX 5700 XT @32Gbps-TB3 (Razer Core X) + macOS 11.1 & Win10 // internal display acceleration  


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Joined: 2 years ago

System specs

iMac 18,3 (27, 2017) + i7 7700k (custom upgrade, shipped with i5) + 24GB ddr4 + Radeon Pro 575 4GB, macOS Big Sur 11.1 + Windows 10 Bootcamp


eGPU hardware

Razer Core X + default TB3 cable + GIGABYTE AMD Radeon RX 5700XT (GV-R57XTAORUS-8GD, 8ГБ, GDDR6, Ret)


Hardware pictures

imagine desk with 5k iMac and Razer Core X on


Installation steps Windows 10

[Through all first six steps egpu TB3 cable should not be plugged in the iMac]


1) Install Windows, bootcamp drivers and reboot

2) Download latest driver from bootcampdrivers.com (both Red and Blue edition works just fine for me)

3) Install drivers following the tutorial from developer (link in the driver archive)

4) Red edition of the driver fakes second display, disable it

5) Shut down the computer, after iMac is off (no need to unplug iMacs power cable) – turn it on

6) Windows will boot normaly, log in and shut down again

7) After iMac is off second time – plug TB3 cable in your Thunderbolt 3 port (I use first of two) and turn it on


[Do not boot in Mac OS or do anything with iMac between steps 6 and 7]


8) Everything should work now, no error 12 or other nonsense, just choose your game or application in windows strange menus, and select high-performance option for the app [your egpu] (just google How to Enable High-Performance GPU for Windows 10 Apps)

9) If you planing on booting from Mac OS to Win 10 – disconnect egpu and unplug TB3 cable before shutting down, when in Windows 10 – repeat steps 6 and 7


Thats all, no need for external display or headless adapter, yes, you will lose some performanse, but look into benchmarks to see the difference


Installation steps Mac OS Big Sur

1) Plug your TB3 cable

Works before or after the booting


Benchmarks (Cool part)

– In Mac OS I use Octane + C4D

Generic scene took 1.25 seconds to render for my rx 5700 xt and 1.05 seconds for my friend, running RTX 2060 in Windows 10 (you should know that metal version of Octane is still pretty raw, so I expect that performance should only go up with future Octane updates)

Other than C4D, I only use generic Adobe apps, and in AE, for instance, I didn't notice any difference


- In Windows 10 Bootcamp

[Lets be real, who prefer win10 for work, other from Autodesk users? So I am, just like any other normal person, use it for playing games]


Cyberpunk 2077 I got +50% performance, when comparing to mine pro 575 

1) rx 5700 xt + internal display: ~40 fps, running game in 1440p with ultra/high settings, and ~50fps in 1440p medium settings (going down to 1080p gives only ~3fps)

2) pro 575 + internal display: ~30fps in 1440p medium/low settings

With external display hooked (is this correct spelling?) into the egpu enclosure, I got only +5% performance (this is 1080p monitor, so ~43fps in 1080p ultra/high settings)

Should notice, that there is strange trend going on with Cyb. 2077 rx 5700 xt performance tests, on YouTube half of the people shows footage with ~60fps (1440p ultra) and other half only ~40fps (1440 ultra). I got no idea as to why, but no, all of those videos uses latest version of the game

For other games I play, I got pretty much the same performance boost.


Didn't do any geeckbench, or other tests, neither in MacOS nor in Windows – didn't see a point



P.S. Hope this peculiar guide helps you, figured it out out of the desperation, after gorgeos iMac 5k display my eyes was almost bleeding from 1080p pixel mess and sorry for my English

P.P.S Привет англоязычным товарищам от российских пролетариев!

This topic was modified 1 year ago
2017 27" iMac 5K (RP575) [7th,4C,K] + RX 5700 XT @32Gbps-TB3 (Razer Core X) + macOS 11.1 & Win10 // internal display acceleration [build link]  

Mini i5 and nando4 liked
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Joined: 6 years ago

@nikolayvasyliev , thank you for your build.  Our users love to see photos so consider adding some.

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