# Cooling and heat sinks

> How computers get rid of the heat their chips produce so they do not slow down or fail.

- Level: Basic
- Topics: Hardware
- URL: https://tidbit.legios.com.ar/cooling-and-heat-sinks/
- In Spanish: [Refrigeración y disipadores](https://tidbit.legios.com.ar/es/cooling-and-heat-sinks/)

Every chip turns almost all the electricity it uses into heat. A laptop processor can produce as much heat as a small light bulb, packed into a square the size of a fingernail. If that heat stays there, the chip gets too hot, so every computer needs a way to move it out: that is **cooling**.

The most common part is the **heat sink**: a block of metal, usually aluminum or copper, pressed against the chip and shaped into thin fins. The fins give the heat a big surface to escape into the air, and a fan blows fresh air through them. A thin layer of **thermal paste** fills the tiny gaps between chip and metal. Gaming PCs and servers sometimes use **liquid cooling**, which carries the heat away in a tube of fluid to a radiator. Phones and fanless laptops just spread it through the case.

When cooling cannot keep up, the chip protects itself by slowing down, which is called **thermal throttling**. That is why a laptop on a blanket feels sluggish, or a phone in the sun gets slow while recording video. Data centers face the same problem at a huge scale, and a big share of their electricity goes just to cooling.

## An analogy

A radiator in an old house: hot water flows through metal folded into many thin panels, so the heat spreads into the room much faster than from a single pipe. A fan in front of it would make it even faster.

## Keep in mind

- Chips turn nearly all their power into heat.
- A heat sink spreads that heat over metal fins; a fan moves it into the air.
- Too hot and the chip slows itself down (thermal throttling).
- Blocked vents and dust are the most common cause of a hot, slow computer.

## Go deeper

- [Computer cooling on Wikipedia](https://en.wikipedia.org/wiki/Computer_cooling)
- [Heat sink on Wikipedia](https://en.wikipedia.org/wiki/Heat_sink)

## Related terms

- [Chip](https://tidbit.legios.com.ar/semiconductor-chip/): A sliver of silicon carrying billions of tiny switches that compute and remember.
- [Laptop](https://tidbit.legios.com.ar/laptop/): A whole computer folded into one portable case that runs on a battery.
- [CPU](https://tidbit.legios.com.ar/cpu/): The chip that runs your programs, one instruction after another, very fast.
- [Server](https://tidbit.legios.com.ar/server/): A computer whose job is to answer requests from other computers, all day, every day.
- [Thermal throttling](https://tidbit.legios.com.ar/thermal-throttling/): A chip slowing itself down on purpose so it does not overheat.
- [Data center](https://tidbit.legios.com.ar/data-center/): A building full of servers where the internet, the cloud and AI actually run.