How To Install 120mm Case Fan

Alaina Yee / IDG

Many of the fries inside a typical PC generate a lot of heat and require some form of active cooling to remain stable. Powerful recent hardware like Nvidia's GeForce RTX 3000-series graphics cards and AMD's Ryzen 5000 processors demand fifty-fifty more than heat dissipation.

System builders usually rely on heatsinks and fans to manage the heat inside a PC. If you're upgrading or edifice a new PC—or your PC is overheating—you may need to install new or boosted fans.

Here's how to identify when you need to supercede a fan and how to do it yourself.

Identifying faulty fans

Ofttimes, a fan will start to emit strange grinding noises or vibrations in its last death throws. Sometimes there is no warning at all, and a fan volition silently come to a stop.

Open up the figurer's example, turn it on, and wait effectually with a flashlight (but effort non to impact anything while the computer is on).

the inside of a DIY gaming PC — This exhaust fan is mounted to the back of the example to vent warm air. Frazzle fans tin also be mounted to the top of the case, while intake fans are usually mounted on the front or sides.

In all simply the lowest-power, passively cooled systems, you'll likely detect at least iv fans: an intake fan, an exhaust fan, a CPU cooling fan, and a ability supply unit (PSU) cooling fan.

The CPU and PSU will be mounted on their respective components, but case fans can be situated nearly anywhere. It'due south common to observe intake fans toward the bottom of a system, usually at the front end, where they can pull in the coolest air. Exhaust fans for expelling warm air are commonly found at the back or superlative of a case.

If 1 of the fans has stopped, check to make certain it's connected. If the fan is connected and still isn't spinning, it volition demand to be replaced.

What you need to know before installing a fan

The majority of cases and PCs sold today will take unused fan locations bachelor. Even if all your fans are working, there'south a practiced chance you'll have room for at least one more than.

If all your system's fans are performance, withal the organization runs hot or unstable, you may want to add more fans. If your case tin't have any more fans, or is getting besides loud, consider liquid cooling. Our guides to setting up your PC'south fans for maximum system cooling and how to tell which direction a PC fan blows can also help with the procedure.

If you demand to supervene upon a fan, make certain y'all find a replacement with the correct size, and connector.

Choosing the right fan

Cooling fans are available in a wide range of sizes and shapes (and colors), from tiny barrel-type fans sometimes used to cool fries, to big axial fans used in most power supplies.

The near common fan sizes autumn in the 70mm to 140mm range, but fans equally large as 230mm are becoming more than popular. Fans with a diameter of 120mm are typical in newer cases.

Look for one with a high air flow (measured in cubic anxiety per infinitesimal, or CFM) and low noise level (measured in decibels, or dBA). This information will be on the bundle or on the product's data page.

a case fan — Fans vary in size, speed, blade shape and color. Some fans even come with congenital-in LED lights, others are more performance focused such as this Noctua Chromax fan.

Larger fans tin usually spin at lower speeds and all the same move plenty of air without making much racket. Some manufacturers incorporate LED lighting into their fans besides.

Maintain positive pressure

When calculation fans to a system, maintaining positive pressure within the case tin forestall dust from being sucked into any open holes or crevices. To maintain positive pressure, y'all need to accept a higher combined CFM for the intake fans than the exhaust fans.

Notation: Nigh fans have small arrows embossed on their frames that show the management of air flow. When mounting, point the arrow towards the inside of the reckoner for intake, and the pointer towards the outside for exhaust.

Power connections

Most cooling fans will connect to a PC with a standard connector of some sort. Mod systems will typically utilise three-pin or four-pin dedicated fan headers, though standard MOLEX 4-pin peripheral connectors are likewise used.

fan connectors — From left to right: A 3-pin connector, a 4-pin connector and a MOLEX connector. Make sure to check what type of fan connector you need before buying your fan.

The analog iii-pin and MOLEX connectors provide power to the fan to make it spin. 4-pin connectors are digitally controlled and let the system to modify fan speeds dynamically.

Many motherboards (and defended fan controllers) will feature an array of three-pin and/or 4-pin fan headers that are placed at different locations around the lath.

Installing a new fan

Notation: Before you install any component in your PC, make sure the PC is powered off.

To remove a faulty fan or install a new one, y'all'll need a Phillips head screwdriver.

If you're replacing a fan, remove the old one past unscrewing information technology from the case and unplugging the cable from the header (or MOLEX connectedness). Y'all tin reuse the screws if your new fan doesn't come with any.

To mount a fan, agree it upwardly to the mounting position and then that the holes for screws line up with the holes in the case. While belongings the fan in place with i hand, use four screws to secure it in place with the other manus.

three case fans — To install a case fan, hold the fan in place with one hand. With the other paw, tighten secure the fan in place with four screws

If you lot just take plastic friction clips belongings a fan in place, simply un-snap the clips, remove the fan, and pop the new one in its place.

Next, attach the fan to an unused fan header. The headers are keyed to ensure a proper connection. Four-pin headers will piece of work with 3-pin fans, merely you won't have control over fan speeds.

4-pin case fan connection — Four-pin fan connections allow your computer to change the fan's speed on-the-fly. Usually, a system will lower speed to reduce noise and increment speed when more than cooling is needed.

Buying a fan controller will give you additional fan headers. Alternatively, you can apply 3-pin/4-pin to MOLEX adapters and connect the fans correct to the PSU. (MOLEX connectors are keyed equally well.)

molex fan connector wires — MOLEX fan connectors are older and don't offer any controls for the fan, but they're easy to connect.

1 final note: Route your fan (and other) cables using appropriate cable management or some nix-ties. This will ensure that cables don't striking the fan as it spins, causing a buzzing sound. Cables that come in contact with fans can also finish the fan completely, or worse, damage the cable.

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