I have that exact same computer except for the motherboard, and it can run most games fairly well. Maybe not at max settings, but seeing as you're upgrading your card, you should be fine for most games.
Alright then, thanks guys but i have one more question am i getting a good geal, average or ripped off? I myself though the whole sha-bang was quite easy and well priced.
The power supply on the ibuypower is just 480 watts
The one in Organs link is a mere 350.
I'm guessing these are generic power supplies too, probably not the most reliable at their limits, so you should be ready to upgrade those as well when you buy a new graphics card.