well you wouldn't be able to play many games, and you defo wont be able to play HD :/
you could play Battlefield 3 on Ultra Settings @1280 x 720
though you will experience a lot of lag,
the rest of the set up is brilliant, just if you buy it think about a better graphics card?
or build your own gaming PC for much cheaper? look on ebuyer? newegg? and buy custom parts.
I Hope I helped?