There are two types of cooling fans may be used for the cooling system: the case fan and the CPU fan. The case fan is designed to circulate cooler air throughout the computer, keeping all components at a safe temperature. The CPU cooling fan is generally located directly over the CPU. It should be connected to the heat sink which is designed to help draw heat away from the CPU. When you're choosing your cooling fan, you'll first want to know its size. Generally, the higher the voltage, the more cooling power you will have, and the better protected your computer components will be. CPU fan is used to cool the CPU heatsink.
Effective cooling of a concentrated heat source such as a large-scale integrated circuit requires a heatsink, which may be cooled by a fan; use of a fan alone will not prevent overheating of the small chip.
