When you're building a PC, after you've finalized the core components, there are many more decisions you need to make — case size, motherboard form factor, type of CPU cooler, PSU wattage, and the number of fans. It's that last part that many new PC builders struggle with, wondering about both the number and the optimum configuration of their PC fans.

While the science behind case airflow can be as detailed a topic as you want it to be, the ideal number of case fans is relatively simpler to tackle.

Intake fans

You need cool air coming in

You might see varying opinions on how many PC fans you should have, but something everyone will agree with is that you should have at least one intake fan. Intake fans bring in cool air into your case, washing over your hot components and helping them stay cool. Intake fans need help from exhaust fans for truly efficient airflow, but we'll get into that below.

The debate between positive and negative air pressure is a tricky one, but in general, you should prefer positive air pressure if you're a beginner PC builder. This means you need to have more air coming in than going out of your case. Hence, two intake fans should be considered the bare minimum if you prioritize good airflow within your PC.

More intake fans will help but the gains will be marginal, even if you're using the best case fans. And at that point, you'll probably be doing it for aesthetics instead of performance.

Exhaust fans

Take the trash out

Exhaust fans are just as important if you don't want the hot air inside your case to simply stay "inside" like a party guest no one wants to hang out with. The cool air from your intake fans gets hotter as it comes into contact with the internal components and needs to be routed out constantly. For this, you need at least one exhaust fan.

This combination of dual intake and single exhaust fans can work just fine in the majority of cases. Some builders use larger cases and install around 6 intake and 3/4 exhaust fans, but they still maintain positive air pressure.

CPU cooler fans

Your cooler has fans too

Don't forget that your CPU cooler also has fans of its own. Whether you're using an air cooler or liquid cooler, you'll have anywhere from 1 to 3 CPU cooler fans installed as intake or exhaust fans. Be sure to take them into account when counting your total intake and exhaust fans. For instance, your case could have 3 intake fans in the front and the 2 fans on your 240mm AIO can act as exhaust fans at the top.

Another configuration could be 3 front intake fans, 2 AIO radiator fans at the top for exhaust, and a single exhaust fan at the back of the case. The best CPU coolers will usually come with high-quality fans that run silently yet feature strong performance.

How many fans are too many?

PC builders can sometimes go crazy with the amount of fans inside their PC. You don't usually need more than the "2 intake and 1 exhaust" configuration to cool your system adequately. But if you're using a high-end processor with, say, a 360mm liquid cooler installed as exhaust, you could easily go with 5 or 6 intake fans, installed at the front, bottom, or side of your case.