Supposing you are to upgrade your system and you already have a ddr3 memory stick, would you buy the asus z97 pro gamer or the asus z170 pro gamer mobo (my cpu will be either 4690k or skylake 6600k depending on the mobo)? The price premium will be $150 if you choose skylake, including new 8gb dd4 memory. Is it worth it? The build will be used mostly for gaming like CoD, Crysis, BF4.