This year has been crazy with new processor launches from AMD and Intel. Intel got things started with a refresh of its existing Skylake architecture, codenamed Kaby Lake, which brings higher clockspeeds and a few new features to the existing LGA1151 platform. AMD countered with its Ryzen processors and the AM4 platform, and then Intel launched its enthusiast Skylake-X/Kaby Lake-X parts with LGA2066 and AMD countered with Threadripper and socket TR4.
With all the new processors, it can be difficult to know what motherboards are the best for each platform. Looking forward, we also know that Intel will launch 8th Gen Coffee lake processors this fall, and while they'll use the same LGA1151 socket as Kaby Lake, the processors will require new 300-series chipsets. But if you're looking to build a new mainstream gaming system with an Intel processor, where the Core i7-7700K and Core i5-7600K remain the fastest gaming chips and also have the most reasonable prices, you'll want to start with a Z270 motherboard.
The jump in features, style, and performance from Z97 to Z270 has been dramatic and useful to enthusiasts of all stripes, far outstripping CPU advancements since Haswell. Most Z270 motherboards support multiple x4 PCIe Gen3 M.2 slots, sufficient PCIe lanes dual-GPU configurations, subtle or changeable color schemes, Realtek’s new ALC1220 audio codec is commonplace, and there are a host of refinements for overclocking. Mounts for 3D-printed add-ons are even starting to appear.
Meanwhile, legacy ports are starting to disappear. USB 2.0 headers and back-panel connectors are getting swapped for 3.0 and 3.1 counterparts. SATA port counts are getting shaved to free resources and space for M.2 and U.2 storage. All the boards here feature at least a pair of M.2 slots, and all are full-speed, 32 Gb/s implementations. The days of SATA may be numbered (at least if they can get prices on M.2 SSDs down to more reasonable levels).
The new Z270 chipset (and other 200-series parts) remain backwards compatible with 6th Gen Skylake CPUs, and 100-series chipsets will also work with 7th Gen Kaby Lake processors. However, Z270 provides four additional PCIe lanes, which is why we're seeing more M.2 slots this round, and you'll also need a 200-series chipset if you want to use Intel's Optimus Memory technology.
While most motherboards will work well, enthusiasts will often want more than the base level of performance and features. After extensive research and testing, these are the best Z270 motherboards.