The Core i7-6700K reached the market under heavy spectating, after the delay of the fifth generation CPUs. Actually, the “Skylake” (sixth generation) CPUs were launched almost simultaneously with the “Broadwell” (fifth generation) ones, considering that those last ones had a few models and little availability. So, the rumors that the “Broadwell” models were never tough for desktop computers in large scale seem to be correct.
When we tested the Core i7-5775C (fifth-generation high-end model), we concluded that it brings almost no performance gain compared to the former generation (except for the integrated video, that was more sophisticated.) Now, comparing the new high-end model, the situation is a little different.
The Core i7-6700K was, on average, between 10% and 20% faster than the Core i7-5775C, achieving a performance boost of 29% on Cinebench, which is a hint that Intel improved the multi-tasking performance. Costing the same of the former model, the Core i7-6700K is an excellent choice for users that need brute processing power—users that work professionally on video editing, for example.
For the home user, however, the situation is different. On gaming, we did not see any performance improvement, which means that a high-end video card is still a best investment than buying a high-end CPU. So, if you will not professionally use you computer for CPU-demanding tasks, the Core i7-6700K has not a good cost/benefit ratio.