We tested the Core i7-6700K CPU, the new high-end, sixth-generation CPU from the Intel Core i family, codenamed “Skylake.” It has four physical cores (plus four virtual ones due to the Hyper-Threading technology) running at 4.2 GHz with turbo clock up to 4.2 GHz, and is manufactured with 14 nm lithography. Let’s see if is it superior to a high-end CPU from the fifth generation, the Core i7-5775C.

The sixth generation of the Core i CPUs from Intel is called “Skylake” and is, like the “Broadwell” (fifth generation) models, manufactured under 14 nm process. Intel uses a “tick-tock” chronogram, where the “tick” represents a new manufacturing process, while the “tock” is a new microarchitecture, using the same process from the earlier generation. Therefore, the “Skylake” architecture represents a “tock,” because it uses the same 14 nm process from the fifth generation, but with a new microarchitecture.

One of the main changes of this new microarchitecture is the compatibility with DDR4 memories (former CPUs were compatible only with DDR3 memories). Because of this, the Skylake desktop processors use a new socket, called LGA1151, which is not compatible with former CPUs.

We already tested two entry-level CPUs from this new family, the Pentium G4400 and the Core i3-6100.

We choose to make most of the benchmarks using a high-end video card, with the integrated video disabled. Being a high-end CPU for desktop computers, the Core i7-6700K will be used, most of the times, with a “real” video card; most users that are looking for a CPU on this price range prefer not to use the video card. Anyway, we also ran some benchmarks to test the integrated video performance.

We compared the performance of the Core i7-6700K to its fifth-generation predecessor, the Core i7-5775C, which we tested before. We did not include any AMD processor simply because it does not offer any competitor to the Core i7-6700K. The most expensive CPU from AMD, the FX-9590, costs less than half the price of the Core i7-6700K, so it would not be a fair (or useful) comparison.

Figure 1 unveils the Core i7-6700K CPU, aside with the Core i7-5775C we used on our tests.

Core i7-6700K CPUFigure 1: the Core i7-5775C (at the left) and the Core i7-6700K (at the right)

Figure 2 shows the bottom of both CPUs. Notice that the side chamfer are located at different positions, which prevents an LGA1151 to be installed in an LGA1150 socket and vice-versa.

Core i7-6700K CPUFigure 2: the bottom of the Core i7-5775C CPU (left) and the Core i7-6700K (right)

Let us compare the main specs of the reviewed CPUs in the next page.