CES 2017 - When we first reported about Intel's new Kaby Lake-based Core i7-7700K hitting 7GHz, it was only with 2 cores enabled - so impressive to see 7GHz, but not so impressive without all 8 cores enabled.
During CES 2017 - overclockers were able to hit 7GHz on the 7700K with all of the CPU cores enabled - using LN2 of course. They hit 7026MHz specifically, with a CPU multiplier of 70, and an FSB of 100.
The new Core i7-7700K has a base clock of 4.2GHz and boost of 4.5GHz, with most people able to hit 5GHz without a problem. The CPU retails for $305 in the US, and obviously changes throughout the world - so for me in Australia, it'll cost $1500 or something ridiculous (jokes, jokes - probably $1200).