The first thing you should focus on is the fan diameter. Most cases should work great with 120mm fans, even those with larger fans pre-installed, because fan brackets can often fit multiple fan sizes.

140mm fans are less popular than 120mm fans. If you own a PC housing that can fit 140mm fans, it can most likely also house 120mm, but this usually doesn’t go the other way around. There are also 200mm and 220mm PC fans, but they’re a niche, and most PC cases do not support them. The other two sizes PC fans can come in are 80mm and 92mm, but these are mostly fans found on CPU air coolers. Virtually zero modern PC cases support 80mm, with some Mini ITX enclosures supporting 92mm fans.

Next, you should decide whether you want RGB or non-RGB fans. In general, non-RGB fans perform better because the main metric they’re optimized for is the overall performance, while RGB fans tend to focus on form over function. That said, the best RGB fans can provide airflow and static pressure levels similar to the best non-RGB fans, but they still lag behind.

While talking about static pressure, PC fans are optimized for two performance metrics: airflow and static pressure. High airflow fans are great at pushing massive amounts of air through the case without obstructions, while high static pressure fans are better at pushing air when there’s resistance in the form of radiators or heatsinks.

In other words, high airflow fans are great at playing the role of case fans, while you should look for high static pressure PC fans if you plan to replace the fans found on your CPU air cooler or AIO liquid cooler.

PC fan airflow performance is measured in cubic feet per minute (CFM). Note that you shouldn’t bother checking CFM numbers on manufacturer websites since those don’t paint an accurate performance picture because they’re measured at max RPM in controlled environments. It’s better to focus on real-life professional and user reviews instead.

Another important PC fan performance metric is rotations per minute (RPMs), representing how many full rotations a fan makes in one minute. More RPMs should equal better performance, but that’s not always true. What is true is that PC fans get louder at higher RPMs. If you want a whisper-quiet set of PC fans, get a model optimized for high performance at low noise levels and RPMs.

Regarding connectivity, most modern PC fans use 4-pin PWM connectors, while some fans, usually budget offerings, come with 3-pin DC connectors. Most modern motherboards come with four-pin fan headers that are backward-compatible with 3-pin DC connectors. Generally, PWM fans are a better option than DC fans.

It’s also worth mentioning that some RGB fans have proprietary connectors, and you’ll need a custom RGB fan controller for them to work with your PC. Two or three-fan bundles generally come bundled with controllers, but single fans do not.

Last but not least, if you’ve got a regular desktop tower, it should work without issues with any PC fan, no matter how thick it is. On the other hand, small form factor (SFF, ITX) cases don’t have plenty of room to spare. If you’re shopping for new PC fans for your SFF build, you should focus on slim fans with slimmer, 0.59-0.66in (15-16mm) profiles that fit inside a compact PC chassis.

The Phanteks T30 Fans are beasts. They leave every other consumer-grade PC fan in the dust regarding airflow performance at every noise level. In other words, They work great as silent fans when you restrict their RPM for silent operation, but they also work amazingly when not reined in, left to push as much air through the case as needed at their maximum speed of 3000RPM.

The T30s are also great both as case fans and replacement fans for air and liquid CPU coolers. When facing obstacles, the Phanteks T30 obliterates any other consumer-grade PC fan on the market. So, if you’re looking to replace fans on your air or liquid cooler, you’ll want the T30.

Sound-wise, the T30 can get pretty loud at max RPM. But since they’re performance is so good, there’s no need to push them to their limits. You can limit their RPM and get both fantastic performance and whisper-quiet operation.

Aside from the price, the only ding here is that the T30 has a bit thicker profile, at 30mm, than regular PC fans, which are 25mm thick. They won’t fit into some compact cases and will make the AIO radiator quite thick if you decide to use them as radiator fans.

If you don’t want to spend a fortune on a set of PC fans, get the ARCTIC P12 Max. ARCTIC has always been a budget-focused brand that offers tons of bang for the buck with every product, and the P12 Max is no exception. These fans can move almost the same amount of air as the venerable Phanteks T30 while selling for half the price. When used as air coolers or radiator fans, their performance is yet again very close to the T30.

The best thing about the ARCTIC P12 Max is that they are optimized for quiet operation. This makes them super competitive at noise levels of 40dBA and lower and allows them to move massive amounts of air while being virtually silent.

While the Noctua NF-S12B redux won’t win any medals, they can position themselves in the middle of the pack performance-wise while outputting only 18 dbA of noise at its max, 1200RPM, which is inaudible in most environments. The results are PC fans perfect for silent builds made of beefy components. The level of performance should be more than enough for most PC builds aside from those featuring a heavily overclocked CPU and GPU that need as much airflow as possible. These fans don’t offer lots of static pressure, so avoid using them as air coolers or radiator fans.

If you’re after a high-airflow fan that’s pretty silent, the Noctua NF-A12x25 PWM and the aforementioned Phanteks T30 are the best choices. Both can push ludicrous amounts of air while being super quiet. With the UNI Fan SL – LCD Wireless 120, Lian Li managed to design a product that delivers both form and function. Performance-wise, these are among the best RGB fans on the market. They can’t match the best RGB-less PC fans out there, but they give any RGB PC fans a run for their money while boasting stunning looks.

RGB implementation here is tasteful and, honestly, gorgeous-looking. Lian Li opted for edge-lit RGB that, in my opinion, looks better than fan-mounted RGB LEDs. The fan was kept RGB-free, which could explain the high airflow performance.

The center of each fan hosts a tiny circular display that can show various information about your PC, such as CPU and GPU temperatures, fan speed, and the temperature of other components, as well as custom images and videos. If you’ve got a fish tank case sitting at your computer table, this is more than a gimmick, offering easy-to-see real-time information about your system.

The main disadvantage of the Lian Li UNI Fan SL – LCD Wireless 120 (what a name) is the price. These are some of the most expensive PC fans around, but at least they offer excellent airflow performance, super attractive RGB implementation, and handy built-in LCDs.

Also, disregard the word “wireless” in the name; the only wireless thing about these fans is that they come with a wireless RGB remote. Another issue here is that they require a custom controller, included in 3-pack bundles but not included if you opt for a single pack.

If you like the overall design but don’t need LCDs, get the LCD-less Lian Li UNI Fan SL – Wireless 120 fans, which cost about 30% less. Those looking for the best-performing RGB PC fans should check the Cooler Master Mobius 120P.