Just an interesting fact. I checked TechPowerUp bios database and compared some specs. It seems that there is no other card with Power Limits so low. Normally, 5700 seem to have around total 150-170W, GPU 150-170A, however this card, probably due to the tiny form factor seems to have 105W/105A limits.
|| Mac mini 2018, i7, 32GB || macOS 10.15.7 || Bootcamp W10 20H2 || Sonnet Puck RX 5700 eGPU ||
Just for research purposes I ‘daisy chained’ Puck RX 560 to RX 5700 to TB on my Mac Mini.
As expected - 2 devices showed up. macOS was a bit ‘confused’ for the first time, but afterwards recognised 2 GPUs connected to the same TB port. W10 20H2 recognised both eGPUs, and RX 560 was working fine without errors while RX 5700 still got ‘Code 43’
|| Mac mini 2018, i7, 32GB || macOS 10.15.7 || Bootcamp W10 20H2 || Sonnet Puck RX 5700 eGPU ||
I have everything working in Win10 1903, but I really want the latest version of windows because of DX12 reasons..
Gonna try this weekend.. any tips/advice before I take the leap? 
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
.I have everything working in Win10 1903, but I really want the latest version of windows because of DX12 reasons..
Gonna try this weekend.. any tips/advice before I take the leap?
Which eGPU do you use?
|| Mac mini 2018, i7, 32GB || macOS 10.15.7 || Bootcamp W10 20H2 || Sonnet Puck RX 5700 eGPU ||
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
.
I tested a bit on macOS. The benchmarks seem to be where they are supposed to be for this card (See the attached screenshots).
There are some developments regarding W10 and the eGPU as well. Now I get ‘Code 43’ on loopback mode (internal HDMI), and ‘Code 12’ when external HDMI on the Puck is connected. I am on 20H2 but this error thing does not seem to be version specific. Only 1909 had ‘consistent’ ‘Code 12’ on any port (int/ext).
System itself loads up fine even without the apple_set_os.efi when on external (but no output and ‘Code 12’). I can see that W10 loads fine and details with RD Client on my iPad.
I cannot get rid of ‘Code 12’ with .efi, HackFlags, disabling 16x or disabling iGPU. The only method I haven’t tried is DSDT. Is there any other method for ‘Code 12’? Port Dance does not help either.
I installed Intel Thunderbolt driver, but no luck either. I can see that the device is connected (See the attached screenshot), but ‘Code 12’ is still there, or Thunderbolt software reports that there was an error and device was disconnected in case of internal HDMI and ‘Code 43’...
|| Mac mini 2018, i7, 32GB || macOS 10.15.7 || Bootcamp W10 20H2 || Sonnet Puck RX 5700 eGPU ||
@susurs, on my mbp 13 2020 pci.sys swap and w10 2004 works fine. Haven't upgraded to Big Sur yet still using catalina
A) 2020 MacBook Pro, i7-1068NG7, 32GB RAM, 1TB, EGPU Razer Core X, Nitro+ RX5700 xt 8Gb, Samsung 49 1440p UltraWide C49RG
Mac OS Catalina 10.15.7, Internal Bootcamp Windows 10 2004 pci.sys swap.
B) 2.7 GHz I7 4 Cores, 16Gb, 1TB MBP 13 2018 TB3 , EGPU Razer Core X, Nitro+ RX5700 xt 8Gb, LG 32UK550
Mac OS Catalina 10.15.2, Ext SSD Windows 10 1903 V1 .295
C) 2.7 GHz I7 4 Cores, 16Gb, 1TB MBP 13 2018 TB3 , EGPU Gigabyte Gaming Box RX580 8Gb, Mac OS Catalina 10.15.2, Ext SSD Windows 10 1803
D) 3.1 GHz I7, 16Gb, 1TB MBP 13 2015 TB2 , EGPU Gigabyte Gaming Box RX580 8Gb
@susurs, on my mbp 13 2020 pci.sys swap and w10 2004 works fine. Haven't upgraded to Big Sur yet still using catalina
Thank you! Did you mean - Is the same Sonnet Puck model RX 5700 working on your system?
|| Mac mini 2018, i7, 32GB || macOS 10.15.7 || Bootcamp W10 20H2 || Sonnet Puck RX 5700 eGPU ||
Regular update on the ‘eGPU Saga’:
I actually decompiled DSDT, edited and compiled .aml on macOS in order to do DSDT override and load it in W10. While override itself succeeded but did not resolve ‘Code 12’, just later I found out it was not necessary for my 2018 mac at all as it already had Large Memory Allocation by default. 
https://egpu.io/forums/pc-setup/fix-dsdt-override-to-correct-error-12/paged/27/#post-92869
|| Mac mini 2018, i7, 32GB || macOS 10.15.7 || Bootcamp W10 20H2 || Sonnet Puck RX 5700 eGPU ||
There is another thread where @Fuzzy mentions getting a Breakaway Puck 5500 to work with 1903. Perhaps you could glean some additional insights there?
I ended up buying one for my son's 2020 13" MBP, and it works great in macOS, but code 12 stopped me on the WinOS side. I'd rather not wipe his drive unless I knew that I could start at 1903, get things to work, and then continue to update to a current release. Sticking to an out-of-date Windows is not an option. Once a get a little time in an upcoming weekend, I'll try to get this to work on an external drive.
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
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