The present invention relates to a heat sink adapted to dissipate heat from a CPU.
In order to enhance the heat dissipation n efficiency of a heat sink, the heat dissipation area must be relatively increased. FIG. 1 shows a heat sink according to the prior art. This structure of heat sink is extruded from aluminum, comprising a flat bottom panel 11 and parallel radiation fins 12 perpendicularly extended from the top surface of the flat bottom panel 11. In order to increase the heat dissipation area, the radiation fins 12 are made as longer as possible. However, due to aluminum extrusion technical problem, there is a limitation to the length of the radiation fins 2.
The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a heat sink, which provides a big heat dissipation area to dissipate heat efficiently. According to one aspect of the present invention, the heat sink comprises a bottom heat sink unit having parallel upright fins, and a top heat sink unit having parallel bottom fins respectively forced into engagement with the upright fins of the bottom heat sink, and two hook plates respectively hooked in respective mounting grooves on the bottom heat sink unit and the top heat sink unit to secure the two heat sink units together. According to another aspect of the present invention, the top heat sink unit has a circular top recess and two locating grooves at two sides of the circular top recess for the mounting of a fan.