With increasing development of science and technology, the processing speed of a computing chip for an electronic device is gradually increased. Consequently, a great amount of waste heat is generated while the computing chip is operated. It is a critical issue to dissipate the heat. For example, a computer host comprises a main board and a display card. The display card is mounted on the main board. Generally, the chip of the display card generates more heat than the main board. Consequently, the heat generated by the chip of the display card has to be dissipated in high priority.
However, for most electronic devices, plural function circuit boards are mounted on the main board in parallel and arranged side by side. Since the airflow for convection is usually obstructed by the adjacent function circuit boards, the heat generated by the chip of the display card cannot be efficiently dissipated away by the existing heat-dissipating mechanism. Therefore, the heat-dissipating mechanism of the electronic device needs to be further improved.