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.
Thunderbolt™ 3 Mini eGFX External GPU Enclosure 240W –
GetUSCart- Razer Core X Aluminum External GPU Enclosure (eGPU): Compatible with Windows & MacOS Thunderbolt 3 Laptops, NVIDIA /AMD PCIe Support, 650W PSU, Classic Black
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Razer Core X Thunderbolt 3 External Graphics Enclosure, 2x 8-Pin (6+2-Pin PCI-e), Wide Graphics Card Compatibility, 650W Power Supply, Mercury
AKiTiO Node Thunderbolt 3 eGPU Enclosure Review
Best External GPU (eGPU) Enclosures
Razer Core X Is the Best EGPU You Can Buy, but Still Has Its Issues
2020 ($1,800) 5K iMac — Will an eGPU improve performance? [Video] - 9to5Mac