Hello everyone! I wanted to share my experience with rx580 egpu for my macbooks.
I was inspired by this post thanks to @itsage , but I couldn't buy exactly what he used, so here is what I have:
1) JEYI Leidian TB3 => m.2 69$
2) ADT-link r43SL 24$
3) XILENCE 400W PSU 25$
4) RX580 preowned 130$
On Mac OS it went pretty smooth - hot plugging worked out just fine. I've managed to test it in dota2, and I'd say it slightly affected performance in comparison to 555x, it's just 40fps for 2880x1800 all max configs with Vulcan API
On Windows I first started with external display and native bootcamp drivers, as far as I have amd dgpu it was also pretty simple. I seemed to be that the only thing I have done is installation of Microsoft display driver instead of 555x and reboot.
But there were some weird things, I haven't got such a good performance in some games like SOTTR, and none of drivers from AMD wanted to install. I tried to manually (from Device manager) update rx580 to the most recent version - and it gave +10 fps in SOTTR so in 2880x1800 it about 30fps on all max settings (except for 4x anisotropic). And dota2 is more than 60fps.
But anyway internal screen didn't work with such a set of drivers until I installed a driver from BootCampDrivers.com - now it works like a charm!
A have also tried to connect this setup to '13-inch, 2018, Four Thunderbolt' and it worked as well, but with external display only
Some notes:
- I had to short pins to jumpstart psu.
- I had to short pins on gpu 8pins power slot as I have 6pins only
- There is an issue with either psu or wires. GPU seem to switch off under high load. PCI power is connected to sata, this wire is getting hot under load, seems like rx580 prioritize consumption from PCI-E (a wild guess). Or the cause is above (6 pins connector). I connected it directly to one of 12 pins of 24pin cable and it seem to work stable until I use overclocking.
Hand made case from 2x 1euro wooden things I found in Flying Tiger
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2020 14" MSI Prestige 14 EVO [11th,4C,G] + RTX 3080 @ 32Gbps-TB4 (AORUS Gaming Box) + Win10 2004 [build link]
Hi. Looking for an advice.
Planning my custom eGPU based on Macbook Pro 2018, i7, 16Gb RAM, RX560X, Catalina 10.15.7
this adapter: ADT-Link R43SG-TB3 PCIe x16 PCI-e x16 to TB3
( https://www.aliexpress.com/item/4000340228749.html?spm=a2g0s.12269583.0.0.3a596079Mdns0n )
ASUS Nvidia 1080ti
and PSU ATX Cooler Master MWE Bronze 600W ( https://www.coolermaster.com/catalog/power-supplies/mwe-series/mwe-bronze-600/ )
Couldn't find any mentions of similar builds here so taking the risk to be the first 
Will appreciate it if you could share your opinion on will this thing ever work, what issues I will face, do I need an external monitor to make this thing work, maybe something else that I could miss...
Macbook Pro 2018, i7, 16Gb RAM, RX560X, Catalina 10.15.7
ADT-Link R43SG-TB3 PCIe x16 PCI-e x16 to TB3
Nvidia GTX 1080ti
PSU ATX Cooler Master MWE Bronze 600W