This is the solution to connect the third monitor: http://www.amazon.com/StarTech-com-External-Video-Monitor-Adapter/dp/B0086359SG/ref=sr_1_2?s=electronics&ie=UTF8&qid=1388206061&sr=1-2&keywords=usb+3.0+to+dvi
I have plenty of USB 3.0 so that is the best option.
Thank you anyway