Dual-Core

Couple questions here.

I know the basics of Dual-Core technology, but I have a few questions about some things that I know companies may hide from the public.

a.) I'm thinking about buying the AMD A64 X2 4400+. The frequency is 2.2GHz. Does this mean both cores run at 2.2GHz, or do they combine the freq some how?

b.) Will I need enhanced cooling from the stock I have now? (i.e. Water; common CPU temp is 27C on my A64 3000+).

Thanks in advance.