A multi-channel module with a plurality of chips is mounted on a multilayer circuit board and has a simple and highly reliable structure cooling system for cooling the heat generated by the chips consuming a large amount of electric power. The cooling system uses in the horizontal direction a coolant supply pipe having straight tube sections and flexible bellows sections alternately disposed in the axial direction of the pipe. The straight tube sections of the aforesaid coolant supply pipe are brought into contact with the upper faces of the chips by a spring force so as to cool continuously the plurality of chips with the coolant flowing in one coolant supply pipe thereby providing a simply structured cooling system for chips. Such a structured cooling system enables the collective assembly of cooling parts for a plurality of chips with only a small number of parts and produces highly reliable effects thereby being able to implement the miniaturization of a main frame computer.
