On Friday, Blackmagic announced it has discontinued their Vega 56-powered Thunderbolt 3 eGPU Pro. However, there are excellent — and upgradeable — options, that won't break the bank.
Plug-and-play macOS Thunderbolt 3 eGPU solution for $120 : r/eGPU
Are external GPUs for Macs viable in macOS 10.13.4? We tested to find out
Razer Core X - Thunderbolt™ 3 eGPU
Review: $300 Razer Core X - the best eGPU for MacBook Pro [Video] - 9to5Mac
MacBook Pro 2016 with a Thunderbolt 3 EGPU – Gamebridge Unityversity
Razer Core X Aluminum External GPU Enclosure (eGPU): Compatible w/Windows & Mac Thunderbolt 3 Laptops - NVIDIA/AMD PCIe Support - 650W PSU
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Best Thunderbolt 3 eGPU enclosures for macOS
Razer Core X - Thunderbolt™ 3 eGPU
Best External GPUs for Laptops
Razer Core X Chroma review: colorful, capable and expensive - The Verge
Best Buy: Razer Core X Thunderbolt 3 External GPU Graphics Enclosure MacOS and Windows 10 Compatible Black RC21-01310100-R3U1
Razer Core X Chroma Aluminum External GPU Enclosure (eGPU):Thunderbolt 3 Laptops at Rs 30000 in Noida