You can 5 box on dual core but you'll be able to display 3 at most and other 2 minimized. At 3 my cpus hover around 98%.. I can display more windows but then it gets choppy. I usually have 3 minimized and 2 visible .. with cpus at around 50-70% depending if you're in major city or somewhere less populated. I'm running amd fx60/gf8800gtx/4gb.