What size radiator do I need to cool my PC?

When it comes to water cooling, the colder the better (to a point that isn't achievable with commercial means). This is the case for AIOs and custom cooling loops. However, there's no sense in going too far, so how much radiator do you need, is the more operative question here, so let's take a look.

In a to use simplified approach, it's generally recommended 120mm of radiator area for every 80 to 100 Watts of heat to be dissipated, in order to maintain a good performance/RPM ratio.

For example, if you want to cool a 14900K processor with a claimed power consumption of 125W, it can still deliver up to 253W in turbo mode, also known as MTP (Maximum Thermal Power). This means that the recommended radiator size is 360mm.

If you're doing custom watercooling where you're adding other components to be cooled, such as an RTX 4080 Super graphics card, and need to dissipate an additional 300W, you should add at least a second 360mm radiator.

Depending on your preferences, you can also add more radiator area to achieve better temperatures or lower fan speeds.

Or, on the other hand, if your case doesn't allow for so much cooling, choose fans with better static pressure, like the RS MAX series. Be aware that these fans are a full 5mm thicker than regular case fans. This could cause clearance problems depending on your case and components. Make sure to measure up to ensure tolerances are correct.

If you are reluctant to do the calculations, or would like an outside opinion, you can use our Custom Cooling Configurator tool, it will be able to recommend optimum cooler configurations for your components.