How Liquid-cooled PCs Work

A heat sink (in gold above) uses lots of surface area to transfer heat from electronic components to the air.

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Heat Sinks vs. Liquid Cooling

Most computers dispel heat with heat sinks and fans. Heat sinks are basically pieces of metal that provide lots of surface area for the air to touch. The chip warms the heat sink, the heat sink warms the air, and the fan moves the warm air out of the PC case.

This system works most of the time, but sometimes, electronic components produce more heat than simple air circulation can dispel. High-end chips with lots of transistors can overwhelm an air-cooling system. So can chips that have been overclocked, or manually set to work at faster than their default speed.

That's where water cooling comes in. Water has a higher thermal conductivity than air - it can move heat faster than air can. Water also has a higher specific heat capacity. It can absorb more heat before it starts to feel hot.

There are two reasons why a computer might need the increased thermal conductivity and heat capacity of water:

  • Its electronic components produce more heat than the air around them can absorb
  • The fans required to move enough air to cool all the components make too much noise or use too much electricity

In other words, there are two reasons why you might need to cool a computer with a liquid instead of air:

  • The components inside your computer need more cooling than air alone can provide
  • You want your system to be quieter

Next, we'll look at the components of a liquid-cooled system and how they work together.