The [[Central processing unit]], or CPU, handles millions of calculations every second, using enormous amounts of computer power in the process. That power generates heat, enough to disable delicate electronic components if it is not dissipated. Keeping the CPU and other computer parts cool is essential for reliable operation and long life. This is done by both integral and peripheral means. Integral means include [[heat sink]]s that increase the surface area through which heat is dissipated, and [[fan (mechanical)|fans]] that speed up the exchange of hot air from the computer parts to cooler ambient air, as well as throttling of computer components in order to decrease their heat generation.
Peripheral means include [[CPU fan]]s that pull and blow air over the processor, and other computer components such as video cards and memory modules. These fans are often variable speed, allowing them to speed up when intensive calculations are being performed by the computer, and slow down when less intense work is being done. Some fans, such as those on video cards and some CPUs, will even shut off during idle periods.
CPUs, like other electronic components, produce varying amounts of heat depending on the frequency and voltage at which they operate. Because of this, it is important to use a CPU cooling device that is rated for the specific CPU you will be using it with. In addition to ensuring that the CPU cooler is rated for the processor speed, it is also important to keep fresh thermal compound (also known as “goop”) between the processor and the CPU cooler base.