As you can see in the image below, the first thing he did was plug the 4K monitor into his 15-inch MacBook Pro with Retina display. Despite appearing to work flawlessly, the implementation is anything but. The Nvidia GT 650M in the MacBook Pro is theoretically capable of 4K output, but OS X is restricted to merely scaling up the laptop’s output, rather than outputting native 4K (3840×2160) resolution.