GideonTech.com has put up a Guide on Peltiers. It is complete with
the run down of how peltiers work and what they can do for the overclocker.

It is simply a "heat pump" that pumps heat from one side to the other when an electrical current is applied to the peltier. A peltier itself is made up of paired up p- and n- type semi-conductors wired in series that are sandwiched between two ceramic plates. As an electrical current is applied to the peltier one side gets...

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