Since that monitor is such a high resolution (2560x1440) you will need either a Mini-Displayport to Displayport cable or a Mini-Displayport to Dual-Link DVI adapter to connect it.
The Mini-Displayport to Displayport cable will probably be quite a bit cheaper than the Dual-Link DVI adapter.
Edit: I just double checked and the U2713H has a Mini-Displayport input, so you don't even need an adapter, just one of these:
http://www.monoprice.com/products/p...=10246&cs_id=1024602&p_id=5991&seq=1&format=2