Brodcast

From other mothers, yes.

i5 6600K + Z170 and save some money

Out of this two: I7 6700k
But as don_svetlio said, ther are even better options.

They will likely perform very much the same. The single core performance is slightly better on the 6700K, but the 5820K has two more cores (and 4 more threads) which might help in rendering. But since you don't do that, 6700K.

well if you purely want to game the yea, but the 5820k has a bit more power when it comes to things like rendering. if you only game then go for the 6700k and overclock it obviously 

Nobody's mentioning cost...
@Brodcast, how much can you get the parts for? If the X99+5820K is cheaper, definitely get it. The single-core performance gap is very small and overclocking makes it a non-issue, while the higher core count makes it a powerhouse.
If the Z170+6700K is cheaper, get it. The higher core count of the 5820K isn't necessary for gaming and that chip is pretty damn fast.

No, if you aren't edditing or running 3-4way SLI, you don't need the superior power of the 5820K with it's extra cores. The 5820K won't help you with games.

thats what he said

Very close. 2 sticks is actually less stressful on the CPU IMC, but 2 slots is not always better than 4. Remember, some board+CPU combinations can run in quad channel, which require 4 DIMMS to be occupied. This means 4 sticks in quad channel would have double the peak theoretical bandwidth of 2 sticks in dual channel. It's why i said "In this very specific scenario" up above, because if he had a board that could support quad channel memory, then 4x4 would offer more performance than 2x8gb. Quad Channel > Rank Interleaving in terms of raw bandwidth. That being said, if you can afford 4x8gb sticks, then you get the best of both worlds on those boards. As you get both rank interleaving AND quad channel.
 
Another thing to note, is that as sticks get higher in capacity, their ability to overclock gets reduced. 8 and 16GB sticks are harder to overclock than 4GB sticks. However, on a dual channel board, 2x8gb 3000mhz memory would actually be faster than 4x4gb 3400mhz memory, due to the additional bandwidth offered by Rank Interleaving, not to mention the ability to write to one rank while reading from another. 
 
Sometimes, memory can just be a little too complicated 

the game aint getting new stuff only skins and boxes if thats what he means and the vac system can sometime be shitty

Pretty sure 5ghz at 1.51V is terrible

i like this guy, i like his voice

Depends on the specific GPUs, but normally one higher end GPU is the better option. 

yeah i am with you its beast