Let's start off with the stuff that won't change for a while. There are four memory channels on the Haswell-E chips and these officially have a limit of 2133MHz. The DDR4 standard actually starts off at 1866MHz but the lower speed will mainly be for those modules sold to enterprise customers that don't need the speed but desire the power savings and the extra bandwidth. Alongside that to the left is the 40 dedicated PCI-Express lanes for graphics cards, SSDs or whatever you want that needs to use those lanes.