Selecting RAM for I5-6600 (non-K)

[rebate]

Here is the build I am working with: http://pcpartpicker.com/p/VXVgGX

I have already purchased the cpu and ssd. Trying to buy ram and mobo now, and was going to go with Crucial DDR4-2133-CL15. Then I found some G.Skill 2400 for cheaper and ended up getting confused on whether or not a faster clock was helpful or if it would default down to 2133 anyway.

All of the skylake cpus have memory listed as "DDR4-1866/2133 @ 1.35V" on intel site. So I am a little confused on why most of the ram I am seeing is 2400 or higher. I was originally under the impression that the mobo decided this. A little clarification would help greatly, thanks.



Gskill ram: http://www.newegg.com/Product/Product.aspx?Item=N82E16820231827&cm_re=gskill_8gb_ddr4-_-20-231-827-_-Product


Crucial ram: http://www.newegg.com/Product/Product.aspx?Item=N82E16820148858&cm_re=CT2K4G4DFS8213-_-20-148-858-_-Product

 

[ComputerSecurityGuy]

Faster clocks are helpful to a point, but diminishing returns kick in. The motherboard will just underclock the RAM if it doesn't support it. I just get whatever the cheapest RAM is. I don't see the point in paying for slightly better binning and flashy heatsinks you don't need.