Your PC can run 2 monitors. In fact, I think you can run 6, 3 on the integraged GPU and 3 on the video card.
Your CPU probably draws around 60w, and the 750Ti has a 60w TDP. The rest of your system will add up to 20-40w. You probably will still have several hundred watts to spare.
A 750Ti is still a very low-end card though, do you have the budget for anything higher?