President's Day Sales?

Cheapest i3 and nVidia

Avatar Gaming I3-32GT Desktop PC - Newegg.com

Cheapest gaming rig with nVidia. AMD processor

iBUYPOWER Gamer Extreme NE650FX Desktop PC - Newegg.com

Otherwise, Bestbuy has a presidents day sale.

But those I listed were already built. If you're building on your own, that's different.

AMD for the price. I really like the i5 though. That's what I have on my personal lap top, but that puts you in the 600+ range quickly.

I've always used nVidia for my graphics, so I had no experience with AMD.