The computer (1) during in operation gets heated up because of the rotating compounds. In existing cooling unit requires external power source to operate, which increase the cost for using that device. The present invention focuses on using phase change material which absorbs the heat during in operation and after operation phase change material starts cool. During cool it attains the real state of material, which doesn’t require any external power source. It obviously reduces the cost involved in the system as well as increase the life of the computers.