CPU

Phenom II x4 9(4/5/6)5.

1^+ I would agree for gaming a phenom x4 955 965 wouldn't bottlneck 480 and it gives you extra cash for other upgrades if your thinking more toward productivity then you'd be more statisfied with a core i5 750

but what about INTEL CORE 2 DUO E8400 or the Intel Core 2 Quad Q8200???

^If you already have a LGA 775 mobo then those CPUs makes sense. But you need to OC those CPU to atch up with 470/480.

to how many??..(I have a core 2 duo e7400 at 2.8 ghz)

The E8400 would be a bottleneck as well, unless you have a nice aftermarket cooler ($50) and OC either of them to 3.6ghz+.

Avoid the Q8XXX series as well.