We're working on a secret project in the TR labs that needed a microATX motherboard as a key component. Despite the wide range of hardware that's come through our doors over the years, though, we actually didn't have a single modern midi-mobo on hand to plug in as part of that project. It turns out high-end microATX motherboards are as rare as hens' teeth these days, too. EVGA is among the few companies still making enthusiast-friendly midsize boards, and the fine folks there came through for us with not one, but two such mobos.
The X299 Micro takes Intel's massive LGA 2066 socket and situates it between four DIMM slots—one for every memory channel available from Skylake-X chips. That means the board supports half of Skylake-X's 128 GB maximum memory capacity, but the design could pay off in better memory overclocking potential thanks to the shorter trace lengths involved. Other fun features include a U.2 port for remote NVMe devices, a wireless card in the box for those who need it, and a spiffy (but optional) I/O shroud that I've installed here for kicks. This board is fairly affordable for an X299 slab o' circuits at $262 right now.
The Z370 Micro is similarly lean and mean, and it's potentially more extreme-overclocking-friendly than its X299 cousin above. This board has two DIMM slots (one per channel for Coffee Lake CPUs) and a refreshingly stripped-down board layout that ensures cooling air can move freely over the high-surface-area VRM heatsinks. All of the power and fan connectors on this board are flat for cleaner cable routing or perhaps less obstruction to extreme cooling hardware, and there's even an auxiliary six-pin connector for providing extra power to massively overclocked dual-graphics setups. This board is available for $190 at Newegg right now (or $170 after rebate).
I'm having a hard time choosing between these boards to build with for our upcoming project, but we'll be reviewing both of them in time. Stay tuned.