System specs
2019 15" MacBook Pro (i9-9980HK [9th,8C,H], Radeon Pro 560X, 16GB) + RTX 3070 FE @ 32Gbps-TB3 (Razer Core X) + Win10
49" Samsung 4K TV (GQ49Q6FN)
Installation steps
The whole setup was pretty much plug and play. All I needed to do was connecting the eGPU to my MacBook and download the latest Nvidia drivers - that's it!
Benchmarks
All benchmarks were made on an external monitor.
3DMark
TimeSpy: 10870
TimeSpy Extreme: 5226
Port Royal: 6611
Fire Strike: 16482
Fire Strike Extreme: 11940
Fire Strike Ultra: 7598
GTA V (max. settings)
4K: avg. 73fps | 1% low 51fps
1440p: avg. 81fps | 1% low 53fps
1080p: avg. 81fps | 1% low 52fps
The lower resolutions didn't make a big difference. It seems like the GPU doesn't work on its full potential in 1440p and 1080p, more like on 50-70%. The benchmark was made while driving through downtown Los Santos. When I drive out of the city my fps go down to around 30fps on all resolutions. The GPU and CPU don't seem to work here with their full potential as well and fans are barely hearable. Still haven't found out the problem here. Please let me know if someone has some ideas for me how to solve it.
Rise of the Tomb Raider (Ultra settings)
4K: avg 61fps | 1% low 47fps
1440p: avg 86fps | 1% low 66fps
1080p: avg 93fps | 1% low 68fps
I benchmarked the first scene in the mountains here, the fps were really smooth and I was experiencing nothing negative during this benchmark.
Shadow of the Tomb Raider (Ultra settings)
4K DLSS off RTX off: avg 52fps | 1% low 33fps
4K DLSS on RTX off: avg 59fps | 1% low 38fps
4K DLSS on RTX ultra: avg 41fps | 1% low 24fps
1440p DLSS off RTX off: avg 67fps | 1% low 39fps
1080p DLSS off RTX off: avg 74fps | 1% low 43fps
Shadow of the Tomb Raider was benchmarked in one of the first scenes in the town during the masked ball ceremony (this is one of the more performance hungry scenes). This title is very playable in 4k ultra settings with DLSS turned on and Raytracing off with steady 60fps or more. During this scene the CPU was working with around 70% of its power in some parts. Maybe that's why the fps difference between the resolutions is not that big. During other scenes the performance in 1440p and 1080p was heading more towards 100fps.
Comments
All in all I'm really impressed with these first results. I didn't run into any bigger issues with this setup and it is working great so far.
The only issue that I still haven't figured out yet is that the GPU doesn't use its full potential in some games like GTA V where the fans are barely spinning, temperature is really low and the GPU works with like 70%.
Please let me know if you have any questions on this build.
Cheers, Cebro
Very cool 😎. Good to know you didn’t encounter any problems with Bootcamp Windows on your MBP.
Which build and version of Windows are you running?
I appreciate a lot for an extensive sharing of gaming experience. benchmarks usually can’t show the real gaming performance on egpu so your comments really means a lot. thanks again 
To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.
.@mini-i5, thank you! And it's version 2004, build 19041.610.
@fotoroman, thank you for your feedback! I've been learning a lot because of the forum here so far, so I'm glad if I can give back in some way by sharing my eGPU build.
@cebro, congrats for this setup. But you can't use the nvidia card on macos right? Maybe is a stupid question, but I have an rx 5700 xt, I saw new 3070 and 3060ti coming...I use mac for work and play games at the evening, so what can I do? I can use nvidia card on macos and after switch on windows without problems?
Thank you very much
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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.I use mac for work and play games at the evening, so what can I do?
Even though the last MacOS version to support nvidia cards was 10.13.4, there were only drivers for the 10 series cards.
Anything after that is simply a no-go.
If you wish to use both MacOS and Windows, your only option is to use an older AMD card i.e. 5700XT and down, or get one of the new Big Navi cards: 6800, 6800 XT, 6900 etc.
2018 MacBook Pro 15-inch: i7 2.6GHz, 32GB RAM - Razer Core X - MSI RX5700XT Gaming X - Windows 10 2004, MacOS Big Sur Beta 9 - Asus PG279QE 27 inch 165Hz display - External 1TB WD Blue 2.5'' SSD USB-C to USB-C connection
@lelejack, It's like Dozeball already pointed out. You can't use Nvidia cards on MacOS. So, if you need the card for both, work and gaming, you should go for a AMD card.
I personally need the card only for gaming, that's why I chose a Nvidia card. Furthermore, Nvidia cards are usually easier to set up in Windows.
And the 5700XT is still a great card. So if you don't need the added performance of the current generation right now, I would suggest to wait until a better availability of the new cards and to get it when the prices drop or even wait for the next generation.
@cebro, you are right. Thanks, with all these innovations my brain is undecided aahaha. Thank you very much guys, I will keep my rx5700xt and 16" 
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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hi, your experience is very cool!
Did you meet error code 12 when you build your egpu.
I find many people meet error code 12 when they use amd, however, if you use nvida, may I avoid this error?
Thanks!
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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