is the i7 5820k 6th gen

Solution
Because of the way Intel labels their "enthusiast" products the 5820k is a Haswell-E or "4th gen" core i-series processor. They generally release the enthusiast version of their chips about a year after the consumer version so they label them as being the next generation, even though technically they're not. The enthusiast chips require a different chipset and CPU socket so you need to buy a different board, one with the X99 chipset.

For gaming the 6700k will be a little faster and it will probably overclock a bit better, but for anything that uses a lot of threads the 5820k will be faster.
Because of the way Intel labels their "enthusiast" products the 5820k is a Haswell-E or "4th gen" core i-series processor. They generally release the enthusiast version of their chips about a year after the consumer version so they label them as being the next generation, even though technically they're not. The enthusiast chips require a different chipset and CPU socket so you need to buy a different board, one with the X99 chipset.

For gaming the 6700k will be a little faster and it will probably overclock a bit better, but for anything that uses a lot of threads the 5820k will be faster.
 
Solution