whatever you do, buy it at a local pc shop, so that whenever you got a problem they will fix it for free (warranty) (if possible a pure pc shop, not something like best buy, doubt they provide proper support if your pc stops working)
you are best off letting them advise you what you wanna get, because not every shop has every GPU, CPU, RAM Stick etc etc
so google for local pc shops, which ones have good reviews etc etc, then tell them how much you want to spend, they will put together a good rig for the money and you are sure that it will run and that you have warranty
for your idea:
CPU and video card sound good, how much RAM? id recommend 8gb+