So you want to connect your laptop to a 4K display? You can do so easily through the Toshiba Dynadock 4K. This is a versatile device that lets you use a USB 3.0 connection to connect your laptop to a 4K display. The built-in video card supports displays up to 3840 x 2160 via DisplayPort or HDMI. There are 6 USB 3.0 ports with two front ports to charge your phone and other gadgets.
The Dynadock 4K is compatible with Windows and OS X computers. It has a space-saving upright design, which helps. You can get yours for under $200 at this time.