The two Zalman coolers both use copper heat pipes to transport heat from their respective heatsink bases up into an array of thin copper fins. The CNPS9500 CPU cooler uses three heat pipes while the VF900-Cu VGA cooler uses two. A heat pipe is a highly efficient conductor of heat. A properly constructed heat pipe has a very low thermal resistance, which is roughly independent of its length (unlike ordinary metal rods whose thermal resistance increases with length). Heat pipes are commonly used to transport heat from one location to another.



Link: PC Perspective