It is common sense that installing an exhaust fan at the rear panel of the case helps to cool all the components of the computer, including the CPU.

However, most people don’t know simple facts about this subject, such as do you need a rear fan if you keep your case open? Do twin-fan tower coolers benefit from a rear case fan as much as one with a single fan? How much better does a high-rpm fan perform than a silent one?

In order to answer those questions, we ran some tests, measuring the temperature difference between the CPU core and room temperature in several different conditions. We will present the test methodology and results in the following pages.

Rafael Otto Coelho is a physicist with a master's degree in Education, and is a college professor in Brazil.