The idea behind an external GPU (eGPU) is straightforward. Take any desktop graphics card, capable of delivering the kind of performance needed to run professional 3D applications, and put it into an external enclosure connected to a PC, rather than housed inside a tower chassis or shrunk down to fit into a laptop. It offers the freedom to use 3D software on devices where the option for powerful graphics hardware otherwise doesn’t exist.
An obvious candidate is small mini-ITX PCs or the Mac mini, which usually have a decent CPU and plenty of memory but rely on Intel’s relatively weedy integrated graphics hardware, which definitely isn’t suitable for high-end graphics tasks.
But it’s absolutely perfect for thin laptops that rely on puny graphics integrated into the CPU. An eGPU enclosure is like a dock on steroids, giving you high-end graphics performance, an external display, battery charging, and perhaps additional USB ports and wired network connectivity too, all through a single cable.