Well, you will have to O.C. it to get it performing any higher. The CPU likely supports higher speeds, but does your MOBO? With Intel, they have XMP which is a pre-set profile that safely brings your memory up to its rated speed. My MOBO has XMP support up to at least 2133 (so it is listed on the board specs without an (O.C.) next to it, and this may not be the case on my board exactly I cannot recall, but lets say it lists 2400 (O.C.) that means there is no XMP profile to achieve that speed but if I want to manually overclock the RAM to 2400 it can be achieved on the MOBO). The listed speed of your RAM is the recommended/maximum running speed, it can safely run at that speed but it doesn't mean your MOBO will support it. If I wanted to get 2400mhz speed on my MOBO, I would have to buy RAM rated to 2400 and overclock it manually up to that speed, it is not a simple task like setting the XMP profile to the XMP RAM speed on the MOBO (as I said 2133 supported on my board with XMP, 2400 is supported with manual overclocking). It would probably not be advisable to take a lower rated speed ram (your 1866) and to OC it to 2133 unless you know what your doing.