Right off the bat we see for some workloads, the Core i7 7740X is barely any faster than the Core i7 7700K. The i7-7740X benefits from a 100MHz higher base clock frequency than the i7-7700K while they both have the same 4.5GHz turbo frequency capability. The i7-7740X also natively supports DDR4-2666 rather than DDR4-2400/2133 of the Kabylake non-X processors.

In non heavily threaded workloads, the Core i7 7740X comes out as the fastest CPU tested, with the Ryzen 7 1800X not having as good single-threaded performance.