The new Core i9-7980XE and Core i9-7960X are 18 and 16-core configurations respectively, with 2.6GHz and 2.8GHz base clocks and 4.4GHz max boost clocks. Hot Hardware says that the both chips support for 36 and 32 processing threads with these 18 and 16 core processors. They both have the same number of PCIe lanes (44), support for quad-channel DDR4 at official speeds of up to 2666MHz (faster speeds are supported when overclocking), 165 watt TDPs, and similar support for an array of Intel technologies. Both chips also leverage the same LGA 2066 socket and X299-chipset as well (not listed). Where they differ is with regard to their base and turbo clocks, total cache, and a minor difference in max TJunction temperature.
Both chips also use Intel's X299 chipset platform and are LGA 2066 socket compatible.
The Core i9-7980XE has 24.75MB of shared L3 cache, 1MB of L2 cache per core, and a TDP of 165W. The Core i9-7960X's details are essentially same, though two processor cores and the cache associated with them have been removed.
The Core i9-7960X has a couple of advantages, however, in that its base clock is 200MHz higher than the flagship Core i9-7980XE and it has higher all-core frequency boost to 3.6GHz, while the 7908XE tops out at 3.4GHz on all cores.
The new chips look good in the benchmarks, posting the highest scores seen to date in heavily threaded workloads. They also offer strong single-threaded performance that outpaces AMD's Ryzen processors.
Power consumption is surprisingly good as well and only marginally higher than the 10-core Core i9-7900X. However, at $1999 for the Core i9-7980XE and $1699 for the Core i9-7960X, as usual with Intel high-end chips they are a bit on the pricey side.