New York: Institute of Electrical and Electronics Engineers (IEEE)
The power dissipation of CPU used in desktop computers has been steadily increasing with time. The tendency for a rise in the CPU capacity resulted at present in increasing heat release to 50-100W for desktop PC. The problem of the CPU cooling consists in restricting its temperature to 80-90degC. Current desktop computers use a heat sink of approximately 60 times 80 mm<sup>2</sup> base area. Desktop computers are typically cooled by heat sinks mounted on the CPU. There is also a fan installed to a heat sink forming an assembly that is attached to the CPU. Air is forced through the heat sink by the fan. The fan-heat sink mechanism will be the key component to solve the heat problems. We deliver a novel copper bead heat sink (CBHS), which is a heat sink combines a sinter hollow copper ball to be its fin, to increase the heat exchange surface area with cooling air. By the other way, we made a coaxial rotor on a fan to enhance the heat transfer coefficient of convection. The goal of this plan is to make a new fabrication process, and the new type heat sink can dissipate the heat effectively. Preliminary result showed that the minimum value for the total thermal resistance is 0.48degC/W under 65 W input power. The heater surface temperature is around 51degC. The results of the bead fan are almost the same by clockwise and counterclockwise. The holes on the bottom cannot bring better performance. The wind can't go through those holes into the sink center. Research work is continuing for the heat transfer enhance of CBHS.