The cards all preform really close to each other temperature and FPS wise. If I were you I would not get a 4GB 760 because the card will run out of power before it runs out of VRAM to use. 2GB is plenty for it. A 500W-650W PSU will run a single card setup just fine. The best tip is to just pick the graphics card that looks best to you or goes with the color scheme of your other components because you won't see a very noticeable difference between them. Hope this helps!