Exhaust vs. Intake - Which Direction Should You Go?

With all the options in PC cooling these days it feels like you have to be an engineer to make a purchase decision. Take, for instance, the possibilities of configuring your fan to push cool air into the chassis, or pull hot air out of the chassis. Which configuration is better? Luckily CoolIT is full of engineers who have devoted their lives to answering questions just like this one, and we’ve uncovered the secrets based on years of research in our expert labs.

An air intake option uses the fan to push cool air into the chassis. In liquid cooling solutions, cool air is blown over the radiator, which cools the liquid inside of the loop and delivers it directly to the CPU. The benefit of this is an optimally cooled CPU. However, this setup does have its drawbacks. With an intake configuration hot air from the CPU tends to sit inside of the case, causing an increase in graphics card, chipset and hard drive temperatures. Your CPU will be nicely cooled, but other case components will see a rise in temperature up to 15OC. Including an exhaust fan elsewhere in the chassis can alleviate this, but it is not quite as efficient as using an exhaust configuration on your CPU cooler to begin with.

Using an exhaust fan connected to the CPU cooler removes the heat directly from the source (the CPU), so it never enters your chassis to cause an unnecessary increase in component temperatures. With exhaust configurations hot air is pulled outside of the chassis, and ideally cool air is brought into the chassis from other locations within the case. Having cool air enter the chassis from a second fan placed elsewhere can efficiently reduce component temperatures within the case dramatically. So what is the drawback of configuring your cooling solution to exhaust air? An average 0°C to 3°C increase in CPU temperature.

At the end of the day, the choice is yours. If you are looking for an overall system performance improvement, you will want to use an exhaust configuration. If you are going to purchase a cooling solution for your CPU, why not allow it to benefit the rest of your components as well? However if your only concern is CPU temperature then you may wish to consider an intake configuration of the fan.

Want more CPU cooling with an exhaust configuration? You can increase the airflow over the radiator using a push/pull configuration to reduce temperatures of the CPU and other components inside the case by an additional 5 to 10 degrees.