Performing millions of calculations per second, a computer’s central processing unit generates heat that can disable its delicate electronics. Effective cooling is a necessity for computers to maintain normal function. Cooling methods may be designed to reduce the ambient temperature of a computer case by exhausting hot air, or to cool specific components (such as the [[Central processing unit|CPU]] or [[Graphics processing unit|GPU]]) and a small area around them (spot cooling).
The most common type of CPU cooling is air cooling. Fans are used to move cooler air over the CPU, allowing the thermal transfer process to work more efficiently. The fan also helps to push air through the case, improving airflow and reducing noise.
Other cooling methods include liquid and immersion. Liquid coolers (often referred to as water cooling) are based on the principle of liquid-to-vapor phase change, and operate much like the radiator in your car or home. They consist of a “water block” that rests on top of the CPU, with a base and thermal paste attached to it. The CPU’s heatplate is connected to the water block via copper or aluminum heatpipes, and the relatively cooler liquid circulating through the system pools over the processor, cooling it.
A passive heatsink is often used on older CPUs and components that do not generate a lot of heat, such as the motherboard chipset. It consists of a metal plate with fins clamped to the CPU’s integrated heat spreader (IHS), which essentially functions as a lid, with a layer of thermal paste between them to help redistribute heat and improve efficiency.