Upgrading/OC'ing RAM question

Currently on DDR3 1600 on XMP 1.3 in UEFI BIOS. I have some basic OC’ing skills…not much.

My board says my max ram speed is DD3 2800+, but has that (OC) after that. Does that mean I have to do some advanced tweaking in my UEFI (more than just XMP) to get the 2800?

I guess my fear is that I buy the 2800 and it only runs at 1600 bcz I don’t know how to get it to run at its stock speed in a stable way.

From my ASRock Z77 Pro4 manual:

Supports DDR3 2800+(OC)/2400(OC)/2133(OC)/1866(OC)/1600/1333/1066 non-ECC, un-buffered memory