I am confused as to why I would purchase RAM at 2400 (or higher) when, according to Intel's spec page, a CPU like the 5820K indicates it only supports up to 2133 (DDR4 1333/1600/2133)? I know, in this case this is DDR4, but the same question for any memory: If my processor only supports up to 1600, why would I purchase RAM over 1600? Thanks.