When we analyzed the Gigabyte Z170X-Gaming 7, we concluded that it was a very resourceful motherboard for anybody building a workstation or gamer computer using a sixth generation Core i3, Core i5, or Core i7 processor.
The Gigabyte Z170MX-Gaming 5, on the other hand, is its budget version. Besides being smaller (because it uses the microATX form factor) and less expensive, it keeps most of the excellent characteristics of the Z170X-Gaming 7, such as the support to SLI (with two video cards) or CrossFire (with three video cards), the USB 3.1 ports, and the high-end audio and Ethernet interfaces. The main differences between the Z170MX-Gaming 5 and the most expensive model are the simpler voltage regulator and the absence of the second M.2 slot.
So, if you are building a desktop computer based on a sixth generation Intel Core i CPU, and you don’t intend to install more than two video cards, the Gigabyte Z170MX-Gaming 5 is an excellent cost/benefit ratio motherboard.