There is more to a loop than just extreme overclocks. They are quieter (as long as you don't unnecessarily ramp up the fans), they cool better (which most use for higher overclocks, but you can just as well use it to extend processor life), and sense of accomplishment.
You need at least a pump, reservoir, tubing, and a waterblock (as well as connections and clamps). Take a look at the XSPC Raystorm kits. The price is worth it, and they come with everything you need.