A random access memory (RAM) is a data storage medium of a computer system for temporarily storing data.  The random access memory is writable or readable at any time and at a very fast write/read speed.  Generally, during the operating system or other application programs are running, the random access memory (RAM) is used as a temporary data storage medium. 
Recently, since the functions of the computer system become more and more powerful, the accessing speed of the random access memory (RAM) is gradually increased.  As such, a great deal of heat is generated during operation of the random access memory (RAM).  If no proper heat-dissipating mechanism is provided to transfer enough heat to the surrounding, the elevated operating temperature may result in a damage of the random access memory (RAM), a breakdown of the whole computer system or a reduced operating efficiency.  For most RAM manufacturers, it is important to dissipate the heat generated by the random access memory (RAM) in order to enhance the operating stability. 
As known, a series of random access memories are packaged into a memory module.  For dissipating the heat generated by the random access memories, a common method attaches a heat-dissipating device onto the surface of the memory module of the random access memories.  FIG.  1A is a schematic exploded view illustrating a memory module and a heat-dissipating device according to the prior art.  As shown in FIG.  1A, the heat-dissipating device includes two metallic plates 10.  The metallic plates 10 are made of high thermally-conductive material such as aluminum.  In addition, the inner surface of the metallic plate 10 is usually coated with a thermal pad 101 (or a thermal adhesive).  Via the thermal pads 101, two metallic plates 10 are attached onto bilateral sides of the memory module 11 and thus the memory module 11 is enclosed by these two metallic plates 10.  Since the thermal pads 101 at the inner surfaces of the metallic plates 10 are in direct contact with the memory module 11, the heat-dissipating efficacy is enhanced.  After the memory module 11 is sandwiched by these two metallic plates 10, the sandwiched structure is fixed by one or more clamps 12 so as to produce the combination of the memory module 11 and the metallic plates 10.  The resulting structure of the combination of the memory module 11 and the metallic plates 10 is shown in FIG.  1B.
Moreover, a fan may be used for further removing the heat generated by the memory module.  FIG.  1C is a schematic perspective view illustrating a heat-dissipating mechanism including the heat-dissipating device of FIG.  1B and a fan.  In addition to the metallic plates 10 of the heat-dissipating device, the heat-dissipating mechanism 1000 of FIG.  1C further comprises a fan 13.  Generally, the fan 13 is mounted on a supporting frame 14.  The supporting frame 14 is disposed beside the memory module 11.  Since the supporting frame 14 is separated from the metallic plate 10 by a gap, the heat-dissipating efficacy is unsatisfied.  Moreover, since the supporting frame 14 occupies much space of the motherboard 1001 of the computer system, the space utilization of the motherboard 1001 is reduced.