1600 Mhz RAM seen as 1333 Mhz in BIOS. why?

[Varangian]

I have 1600 Mhz RAM installed in my GA-Z68X-UD3H-B3 motherboard.

It seems BIOS is reading it at 1333 Mhz.
Now, I can "set" it to 1600 Mhz, but isn't that overclocking it?
Also, if BIOS is reset for whatever reason, it defaults to 1333 Mhz.

(see screen grab)

Speed is my goal, but also STABLE system, so I'd rather have it run natively at 1600 Mhz.

Any ideas what is happening here, or how to rectify?

Thanks!

 

[Going Bald]

Because the base ram bus speed of the 2600K is 1333MHz.
If you want it to run at 1600MHz, you will need to OC your cpu a bit.

 

[roguedesigner]

Change XMP to Profile 1 and all will be well.