2020 iMac 5K (RP5500XT) [10th,8C,K] + RX Vega 64 @ 32Gbps-TB3 (Razer Core X) + macOS 10.15.6 & Win10
For some reason it is much harder than I thought and I have tried many combinations (including 1903, 2004; many different version of driver). Eventually found the one presented in below which will be working and hopefully it is helpful for you. If Windows will be your daily driver... I cannot say I recommend this build since without the dGPU driver, your amination / video decoding in the iMac display is kind of laggy.
Thankfully it just works.
If you would like your Parallel Desktop (v16) to take advantage of the eGPU, make sure you click "prefer using external GPU" and place your gaming window in external monitor.
1) Install Windows 10 Pro using build 17763.379
2) Let bootcamp install driver and does it thing (I strongly recommend you to backup the graphic driver for 5500 XT as it seems impossible to install the correct driver for it using any driver hosted online). Enable administrator account. Disable Windows Update via group policy
3) Install automate-eGPU EFI. I am using a USB drive, make sure you choose "NVIDIA" as GPU vendor. And apply for the Catalina fix mentioned in post. From now on, always boot into Windows via EFI
4) Connent the eGPU. Use the EFI (and it will always say eGPU not detected, don't worry) to boot into Windows safe mode to run DDU
- IMPORTANT - when you run DDU in future in case of screw up, make sure you are always booting in safemode via the EFI.
- Tips: it appears that the build of Windows 10 has an issue with not accepting password, you will want to enable admin account so you can log into Windows
- In DDU, select all box for AMD and NVIDIA, run twice the clean and do not reboot and finally clean and reboot (just to make sure)
5) Diable the dGPU by its whole PCIE Root Port and internal Wifi via device manager. Install the latest Thunderbolt Driver (for some reason it is crucial). Reboot
6) Install the Adrenalin April 2020 Red version (do NOT tick the factory reset box). Your external display should now works but only for this boot.
7) Reboot. Your eGPU should be not recognised again. Go to device manager (sort by connection) and you will see your eGPU is recognised by the thunderbolt driver as "HSA component", uninstall device and tick the "delete driver software".
- For some reason it is important to update the TB driver for the AMD driver to configure correctly the eGPU during installation; however with this TB driver your next boot will always mis-recognise your eGPU so you need to delete it.
8) Reboot. Enjoy.
Lastly I would like to add that your journey might not as smooth as mentioned in above. For instance, I ran into Windows Repair at step 6) when the driver installed > reboot, external display is showing login>BSOD and Windows Repair (which I cancalled) then I started with steps 4) again. Unfortunately I cannot guarantee the step above is 100% reproducable result, but I hope it might help you.
I have been running this setup not for very long, and occasionally you might boot into Windows (with EFI) without successfully recognising the eGPU, sometimes it will just resolves itself without making any changes after few reboots. Not sure where the problem is, but this setup will not be a stable build.
Post to reference:
(unliked mentioned by OP, I do not have to disable the eGPI audio)
I really wonder why the AMD eGPU support is so shit on windows that you have to jump through all these ridiculous hoops to get it to work. Just confirms that I will buy nvidia eGPU no matter what.
It's nice you got it to work though
Thanks for the nice build report. Good info.
I ask because I have one, but am also considering bumping up my gpu processing power with a eGpu. I wonder if you can get your RX Vega to work like two Nvidia cards would work in a pc. Guess I may have to ask the Otoy team but it is certainly an interesting prospect. Those who shelled out big cash to get the Mac Pro last year might also be able (theoretically) have multiple GPUs to work with the new Octane X.
I'd be interested to hear from anyone else trying Octane X on a Mac.
For reference, a couple months ago I ran the initial resolution-limited version of the Octane X demo with the (4) standard benchmark scenes on my 5700 XT eGPU setup.
@mini-i5, SWEET! checking the build link out now. Just trying to find out from Otoy if octane will recognize 2 GPU's on a Mac. It should work but I know the plug-in has some limitations depending on whether you have enterprise or a regular subscription.