Intel created quad-core "Kaby Lake-X" processors for its latest HEDT platform as they provide an affordable entry to the segment, with a potential to upgrade to larger 6-core, 8-core, 10-core, 12-core, 16-core, and even 18-core processors. The two "Kaby Lake-X" SKUs launched are merely adaptations of the Core i7-7700K and i5-7600K for the LGA2066 socket, as they feature just 256 KB of L2 cache per core (and not 1 MB per core of "Skylake-X"), just a dual-channel DDR4 controller, even though the socket supports quad-channel memory; and just a 16-lane PCIe (while the platform supports up to 44 lanes). While the Core i7-7740X and i5-7640X are priced more or less on par with their LGA1151 twins, motherboards on this platform aren't cheap, with the cheapest LGA2066 motherboard priced a little over $200. GIGABYTE senses an opportunity in all this, in launching the Aorus X299 Gaming. This LGA2066 motherboard only supports the i7-7740X and i5-7640X, and no other LGA2066 Core i7 or Core i9 chip.
Built in the ATX form-factor, you could be mistaken for thinking the Aorus X299 Gaming to be a mainstream-desktop motherboard based on the Z270 chipset, were it not for the unmistakable LGA2066 socket. The board features four DDR4 DIMM slots, all towards the east of the socket, and so it only supports up to 64 GB of dual-channel DDR4 memory. On boards with four DDR4 slots, yet quad-channel memory support, you typically find the memory slots split in groups of two, on either sides of the CPU socket. This "Kaby Lake-X" specificity carries over to even the PCI-Express slots, where there's only one slot with full x16 wiring, the second slot only features x8 wiring, while the third slot is x4. You can use up to two graphics cards in multi-GPU, where the first and second x16 slots configure as electrical x8/x8.