Screen Blacking Out Randomly

Hello all,

I just recently built a gaming PC and things have simply not been going well for me. I was playing Civ 5 with some friends online and my screen randomly went black and there was no way out of it, so I had to force a shutdown. I tried again and the same thing happened. I then figured maybe something was wrong with my GPUs, so I ran the Heaven DX11 Benchmark and made it all the way through. Shortly after finishing and after closing the program, the screen went black again. I'm getting extremely stressed out with this machine already and I just built it. I'm starting to regret even doing this and just sticking to a prebuilt machine. Does anyone have any idea what could be wrong? I have 2 Evga GTX 680 Superclocked signatures, an Asus Rampage IV Extreme motherboard, and an i7 3930K. I put my specs as my sig but I'm not sure if it worked..