External GPU for computers that can’t have full size video cards installed internally, like a [[Mac Mini]] or a laptop. Usually connected over Thunderbolt 3.
from this MacRumors thread, which has more to say:
I assure you that the Sonnet eGFX Breakaway Box 650 and the Sapphire Pulse Radeon RX 580 card combination is an effortless no-brainer on the Macs and Windows 10 PCs I have tried.↩
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