I just got a new computer with an i7 4790k and GTX 770, however am very disappointed with performance. I was getting bad framerates on League of Legends on Very High and just now I booted Mirror's Edge, an old-ass game, and it was running at a very low framerate on high settings. A friend suggested it sounds like the graphics card isn't being used, and sure enough using GPU-Z to monitor while playing Mirror's Edge the GPU was under 0% load (it was still available to monitor though so I guess it's connected fine). I also definitely have the latest drivers installed.
Monitor-wise I have a Samsung 1080p monitor connected over VGA (only came with that and it seemed to look fine) and a Sony 1080p TV over HDMI for sound and extra screen space, however I only game on the one monitor. Both are plugged into the motherboard jacks so I could use Intel's software to manage their relative positions etc. I would't think this would affect much though right? I would assume the graphics card provides extra processing no matter what is plugged into it.