It appears as if Intel’s upcoming Core i7-7700K Kaby Lake CPU is actually running slower than the previous generation Intel Core i7-6700K Skylake in like-for-like benchmarks.
The Intel Core i7-7700K is clocked higher right out of the box, running with 4.2 GHz base clock and 4.5 GHz boost clock. That’s moderately faster than the 4.0GHz base, 4.2 GHz boost on the i7-6700K. As a result, in the series of benchmark tests performed by Chinese site EXP Review, the Intel Core i7-7700K came out unanimously on top. It was 7.4% faster at single-threaded performance and 8.88% faster during multi-threaded benchmarks.
That’s all well and good, but when you take account of the difference in clock speeds it’s not so impressive. In fact, if you clock both the Core i7-7700K and the Core i7-6700K at the same 4.0 GHz clock speed, the new Kaby Lake chip actually runs slower than the older Skylake CPU. Single-threaded performance is most affected, running 0.86% slower, while multi-threaded is practically imperceptible at 0.02%. Therefore, running clock for clock, according to the benchmark results the new processor is in fact slower.
A disappointing result, to be sure, and probably one of the most minor CPU iterations we’ve yet seen. There’s not really anything lost from just overclocking a Skylake chip to 4.2 GHz, achieving potentially faster performance.
From the looks of these benchmarks Kaby Lake CPUs are very much refinements rather than anything that screams must buy.
Source: Core i7-7700K 4-Core 4.2GHz News - Benchmarks Show Intel Core i7-7700K Like-For-Like Clock Speeds Slower Than Previous Gen