A personal computer comprises a heat dissipation plate installed on a floor of its case, a motherboard disposed apart from the heat dissipation plate by a predetermined distance, and a daughter board disposed in such a manner that the motherboard is positioned between the heat dissipation plate and the daughter board. The daughter board is mounted with a central processing unit which generates heat. The motherboard is provided with a hole. A heat dissipation block extends from the heat dissipation plate through the hole in the motherboard, and is connected to the central processing unit through a heat conductive coupler. This forms a heat dissipation path which passes through the central processing unit, the heat dissipation block, the heat dissipation plate, and the case. In addition, another heat dissipation block is interposed between a keyboard and the daughter board so that another heat dissipation path can be formed through the central processing unit, another heat dissipation block, another heat dissipation plate, and the keyboard. A heat pipe may be connected to a heat dissipation plate.