What are realistic Intel old gen to new gen performance improvements?

[DELTAprime]

With the 7700k coming soonish and a bunch of "leaks" that suggest it will be a huge leap forward in performance I was wondering what type of performance improvements normally are seen going from an old generation 4 core 8 thread unlocked Intel CPU to the next generation 4 core 8 thread unlocked Intel CPU? I've heard anything from no improvement to massive improvements so I'm just wondering.

[SCHISCHKA]

i believe its more cache, more clock speed, less power consumption. but not huge improvements. I think they are using a smaller die but no major architecture changes

[jeffmeyer5295]

It really depends on the generation, they all focus on different things(power consumption/single core clock speed/cache) . So it is pretty hard to judge or answer with certainty. I might also be totally wrong. 

[Djole123]

Well, if we go by "Process-Architecture-Optimisation" thing, Kaby Lake is Optimisation, which means slight improvements over Skylake.