What type of games are wanting to play? Strategy, FPS, Indie, etc. It helps to know what you're into so the parts can be picked, as Strategy games relies heavily on a CPU, so does MMO type games. Indie games can be played on a toaster, FPS mostly needs a more beefier graphics card.
Your budget is $700, that's going to be rather hard considering you're trying to budget a monitor into that. If you have a TV with HDMI, or a pc port, you could use that until you get more money for a display.
Edit: To save costs and put money into what matters, you can drop the audio card as well, onboard audio is fine until you want to spend more and upgrade, unless you're anal about audio over graphical power