HELP:how to calculate proper cpu power?

[Joe Forster/STA]

Yeah, the effective performance (virtual frequency) and the nominal frequency increase (or decrease) in parallel. (On a given processor family, that is. With a next-generation CPU, a lower nominal frequency can have a higher effective performance: better optimization, more pipelines, more cores, more parallelization etc.)

As for "64" in the CPU name, it means a 64-bit CPU (rather than the previous generation of 32-bit CPU's); "FX" is some subtype (I'm not up-to-date with current CPU namings; see AMD's homepage for more infos). If you buy such a CPU, make sure to buy a motherboard that explicitly supports it (the motherboard manual and the product page at the manufacturer's site has such a list).