ram speed in motherboard

joho5

Honorable
Dec 28, 2013
222
0
10,710
if my motherboards specs say this:

4 x DIMM, Max. 32GB, DDR3 2133(O.C.)/1866/1600/1333/1066 MHz ECC, Non-ECC, Un-buffered Memory

Does that mean I can put 2133 ram in there, or it has to be an 1866 overclocked up?

thanks