For years, we saw trade show demos that linked laptops to powerful desktop graphics cards via external Thunderbolt enclosures. Those demos were neat, but we hadn't seen the approach replicated in the real world—until now. An intrepid user in the Inferno Tech forums has built a similar setup using off-the-shelf parts. The rig connects a MacBook Pro notebook to a desktop GeForce GTX 780 Ti using an external Sonnet chassis with a Thunderbolt 2 interface.
There are, of course, a few limitations. The Sonnet enclosure is restricted to Gen2 PCI Express speeds, and its x16 slot has only eight lanes of electrical connectivity. Also, the Thunderbolt 2 interface is effectively capped at 20Gbps in each direction, making the pipe to the graphics card much narrower in a typical desktop. Despite those challenges, the system seems to perform pretty well. Performance is claimed to be 85-90% of what the GTX 780 Ti achieves in a desktop machine. Here's a video of the setup in action:
Impressively, the rig is "completely plug and play" using a standard Boot Camp install of Windows 8.1. Nvidia's normal desktop GeForce drivers work without issue, and so does MSI's Afterburner tweaking software. The user even set a custom fan profile for the card.
So, why haven't we seen anyone doing this before? Cost. The Sonnet enclosure sells for nearly a grand on its own, and that's without the necessary Thunderbolt cable. The setup also requires an external PSU to power the graphics card, which isn't terribly elegant. It's exciting to see the promise of external Thunderbolt graphics realized using standard hardware, though. If only there were more affordable solutions along the same lines.