Experimental and numerical studies of the thermal performance of a variety of heat sinks withdifferent base plates for increasing heat releasing rates in CPU have been take on in this research.The parameters of heatsink geometry such as fin pitch, fin thickness, base plate thickness, andbase plate materials are optimize for better the thermal performance of heat sink. The thermalmodel of the computer system with a single cut plate-fin heat sink design and other fin geometryfin pitch, fin thickness design is created using ANSYS (for preprocessing) and the simulation iscarried out using ANSYS (for solver execution and post processing). The experimental results ofgeometry fin pitch, fin thickness, base plate of heat sinks have been compared to a fluiddynamics code. In this research work the fin thickness is varied from 3mm to 5mm and also thefin pitch is varied from 1.5mm to 3.5mm. The aluminum, copper and carbon carbon composite(ccc) materials are used as base plate of heat sink. The base plate thickness of 2.5mm and 5mmare used.