Thunderbolt 3, when properly implemented, provides enough bandwidth to make external GPUs possible.  The rather large Devil Box dock offers all the connectivity generally found in a docking station but can also handle even the most recently released GPUs.  Overclockers Club tested out the effectiveness of the Devil Box with an RX 480, comparing the performance of the card when installed internally and externally.  As you would reasonably expect the performance is slower over Thunderbolt, by a fair margin in most cases but not as much in the DX12 Ashes of the Singularity.  Drop by to see the full review and ponder if adding an external desktop GPU to your laptop is interesting enough for to you invest in.

"If you are using a laptop, you get single connection to everything you need via Thunderbolt 3. External storage, connecting USB peripherals, Gigabit LAN connectivity, display output, and charging all through one cable. Pricing will come in at $375 US for just the Devil Box enclosure and included Thunderbolt 3 40Gbps cable. Add in the cost of a good, solid $200 GPU and you fast approach $600."

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