^ That's wrong.
Your motherboard will run with the DDR3 1600 just fine. That RAM kit was designed for LGA 1366 specifically.
Run CPU-Z and it should show up as running at 800Mhz. It's DDR ( double data rate ) so showing as 800Mhz is correct. It will show as 667 if it's running at DDR3 1333 speeds.
So CPU-Z at 800Mhz and 7-7-7-24 2T.