Hi newcomer and welcome to the Tom's hardware forum.
For an advice about the mobo, we need know all the components of the rig. Now, for the OC, you are right, means overclock, means that you need set all the specifications of your RAM manually in the BIOS.
How is Asus compared to other brands? And what exactly does that mean when is says next to the supported RAM O.C. (overclock)?
i have always had good luck with ASUS mobos, sometimes they're pricey,but you can find a reasonably good mobo for under $100,but i haven't looked into it recently. you might find a used one that's got good specs,but u dnt have to go that route,and OC does mean Over Clock, that mobo you've checked out is actually a pretty good one,im goin toget the same when i build myself a new tower,you're going down the right path...