The Z270 chipset and friends
To go with the desktop Kaby Lake lineup, Intel is introducing several new chipsets to go with it. The one of most interest to enthusiasts, however, will likely be the Z270 platform. Z270 retains the same LGA 1151 socket that underpinned Skylake CPUs, so one can mix and match Z170, Z270, Skylake, and Kaby Lake CPUs in whatever mind-bendingly complex compatibility matrix that would produce. It'll all work together. You can see just how MSI and Aorus are implementing the Z270 in our full reviews of the MSI Z270 Gaming Pro Carbon and the Aorus Z270X-Gaming 5.
In a 200-series motherboard, however, Kaby Lake CPUs will boast out-of-the-box compatibility with DDR4-2400 RAM, a nice little boost that came along with Broadwell-E CPUs last year. Z270 will also give motherboard makers four more PCIe 3.0 lanes from the chipset to pair with storage devices and peripheral I/O controllers. That means a total of 24 such PCIe 3.0 lanes from the Z270 platform controller hub and 16 more from a Kaby Lake CPU. In a world where more and more devices hunger for PCIe lanes, that small update could prove quite handy. Intel hasn't updated the DMI 3.0 interconnect between the processor and chipset, however. That link still offers bandwidth equivalent to about four PCI 3.0 lanes.
Despite the broad cross-compatibility among Skylake and Kaby Lake CPUs and 100-series and 200-series chipsets, there are some advantages to going with Intel's latest and greatest. Pairing a Kaby Lake CPU with a 200-series motherboard is the only way builders will be able to take advantage of Optane Memory, a new intermediate data-caching product that'll sit somewhere between main memory and bulk storage. Optane Memory could be the first appearance of Intel's 3D XPoint technology in a consumer product, but we know next to nothing about it right now aside from the fact that it can only be used with Kaby Lake CPUs and 200-series chipsets.
Optane Memory superficially sounds like a much-improved reinvigoration of the Turbo Memory solid-state caching product that made a rather inglorious appearance in some laptops several years ago. We'll hopefully learn more about this technology soon and get an opportunity to give it a spin, but Intel seems to think Optane Memory will have the greatest benefit for systems that rely on hard drives for primary storage. Given the increasing prevalence of large NAND flash SSDs as the primary storage devices for enthusiast desktops, we'll have to see whether Optane Memory is a valuable addition to those systems.
PCs with 200-series chipsets inside will also gain support for Intel Smart Sound technology, a dedicated DSP that can work with Windows 10 to enable features like system wake-up with Cortana. Compatible 200-series chipsets and Kaby Lake processors with Intel vPro support will also be able to work with Intel Authenticate technology, a hardware-enforced identity management system that can require the user to log in using any of several factors. Intel says it's working with consumer software providers to add support for hardware-enhanced security measures for applications like password managers, touch-to-pay with biometrics, and more. The availability of those features will likely depend heavily on what a given system integrator chooses to include in a PC, so we'd expect to see them mostly in laptops where tight integration of the necessary hardware can be guaranteed.
As you can see from Intel's comparison diagram of all of its new desktop chipsets, only the Z270 chipset will permit the PCIe 3.0 lane-switching from the processor that one might want for CrossFire or SLI setups. The remaining feature differences between the chipsets largely boil down to peripheral connectivity, RAID support, and management features for IT departments. Given the wide range of price points that motherboard makers were able to hit with Z170 boards, we'd expect that outside of the most budget-limited systems, builders will be able to choose a Z270 motherboard at the price that best meets their needs with time.