questions for getting a new CPU?

[hojhak]

I am building a computer from the ground up and I was looking at Intel CPU's that are 2011 socket type. While looking at the 5280k, I saw supported memory at DDR4-2133, DDR4-1333, and DDR4-1600 and memory slots at 4. Can someone elaborate? I thought that was up to what motherboard I chose.

 

[lazyboy947]

That is the stock frequencies that the cpu supports, and what the motherboard will run ram at default. The board supports higher frequencies by overclocking, but even those frequencies are not guarenteed, even the labeled speeds on the ram itself. It comes down to the quality of the memory controller on the cpu and the board on how well it handles the overclocked ram past the intel stock speeds

I think the lowest consumer ddr4 speed is 2133, but ram can be downclocked, but most systems will start at 2133 until changed, by overclocking or using the XMP profile, which changes the bclk normally on x99 and can effect cpu stability