A heat exchanger includes a heat transfer surface to transfer heat to or from a working fluid, a manifold region with a plurality of internal walls defining a plurality of inlet and outlet passages, and a heat transfer region disposed between the manifold region and the heat transfer surface. The data processor includes a plurality of cache memory units, wherein only a cache memory unit that stores a demanded instruction is enabled, while other memory units are disabled. Hence, the three-dimensional fluorocarbon microstructure can be fabricated which comprises a complicated structure that has conventionally been hard to fabricate. A more rigid comparison is made on the list of possible locations comprising a coarse match and a fine match. Because the two die are coupled to each other on opposite faces of the interposer, each package is extremely space-efficient. When the overlay control receives a release focus message, the overlay control passes its state back to the replacement control and is destroyed.