IMHO ,owing to the KHX1600C9D3 didn't have XMP profile ,
so the KVR1333D3N9/4G and KHX1600C9D3/4G is exactly same memory sticks if running @ 1333 v1.5 .
and you shouldn't overclock the KHX1600C9D3/4G (@1600 v1.65) together with KVR1333D3N9/4G.
If running at 1333 v1.5 ,you shouldn't meet any problem, though.
Are you sure you had given the exactly model of your hyperx ddr3 ?
some of the model has xmp profile, and the mobo might auto overclock your whole system , including CPU.