What kind of games are you playing when your computer blacks out? The integrated graphics will be able to handle facebook games and flash games and videos, but it is not designed to work with any GPU heavy games.
Basically the display port works exactly like HDMI, you just have to have the right cable and connectors.
I have only been playing league of legends, not a heavy graphics game. Is it really worth going for a graphics card? I don't really care for nice graphics too much and I am not a big gamer, so would it be worth having? If I do get one I'm thinking about going with this EVGA(NVIDIA) card;http://www.newegg.com/Product/Product.aspx?Item=N82E16814130625
I think I can afford it.