Mini-ITX motherboards need to make the most out of the space available, especially with Intel's Z170 platform offering so much PCIe connectivity. Asus is doing its darnedest to use every inch with the Z170I Pro Gaming motherboard.
Asus managed to pack many of its larger motherboards' features onto the Z170I Pro Gaming. Pretty much every modern storage interface is supported. Four SATA ports (two of which sit in a SATA Express connector) adorn the board's surface, and an M.2 slot on the back of the board is joined with four lanes of PCIe 3.0 connectivity. A USB 3.1 controller from ASMedia provides 10 GT/s transfer speeds through a pair of Type-A connectors.
Everything else you'd expect from a premium mini-ITX motherboard made its way into the Z170I Pro Gaming, too. An EMI-shielded Realtek ALC1150 codec with isolated traces and fancy capacitors handles analog audio, and Asus bundles its SupremeFX audio software suite, too. Intel Gigabit Ethernet and an unidentified 802.11ac MU-MIMO controller push packets, and a pair of DIMM slots can hold up to 32GB of system memory.