PC Fan Making Rattling Noise (10 Causes, Fixes)

Your PC fan is rattling as if an object is hitting the fan blades when they rotate.

It sounds like a big old engine instead of a modern computer, and it’s hacking you off.

Other than being annoying, it’s getting you worried.

You want to know why your PC fan is making a rattling noise and how you can fix it.

A rattling PC fan can have various reasons, from reaching your CPU limit to the fan’s speed configurations and physical placement.

Read on to see which one is causing yours and find a way to troubleshoot it.

PC Fan Making Rattling Noise (Causes, Fixes)

1. Dust And Grime Buildup

Dust and debris are two likely culprits for grinding fan noise.

When your fan blades grow a fur of dust, its spinning mechanism gets blocked.

As a result, the fan struggles to keep working and starts producing a “help-me” growl.

Why not help it out by clearing all the dust?

All you need is a screwdriver to open the chassis, plus a compressed air can, electric air duster, or anything similar to blow out the dust.

You can also take a soft, lint-free microfiber fabric to wipe away the remaining grease.

This technique will likely solve your problem, especially if you live in a dusty area, smoke, or keep pets around the computer.

Remember to apply it to all your PC fans, including the ones on your GPU, CPU, RAM, and power supply.

If you’ve placed a dust filter inside the tower, clean that, too.

Note: If you have trouble taking your PC components apart, refer to the instructions of the manufacturer manual.

You can also put the job into a professional’s hands.

2. Loose Attachment

The fact that your fans look clean and healthy doesn’t mean it’s also securely attached to the mount.

A loosely attached fan makes it wobbly while spinning, sometimes producing a terrible racket.

Open the unit and fasten the screws and pins on the fans.

Thrust the fan grommet down to ensure it hasn’t come loose.

(It’s a foam or rubber sheet or pin placed between your fan and the mounting place to rescue the vibration sound.)

If your fan doesn’t have a fan silencer, consider buying one since it’s pretty efficient at reducing your fan noises.

3. Uneven Computer Surface

If your computer sits on an unbalanced, skewed surface, its internal parts, including the fans, may have a hard time operating properly.

For the fan, it may cause the vanes to wobble, bend out, or even rip off their mount.

They may get in each other’s way, making a loud rattling or knocking sound.

If you’re lucky enough, placing the PC on a flat surface or moving it around can do the trick.

However, if you’re too late to enhance the placement, permanent damage may have occurred to your fan that needs replacement.

4. Extra Loads On PC Tower

Some users tend to place their headphones, external hard drives, adapters, etc., on the tower.

Others even use it as a stand to put decorative items.

Placing other things on your desktop PC can sometimes press the shelf towards the fan, making the vanes scrape along the walls.

The noise even becomes worse when the resulting vibration transfers to the objects and starts shaking them.

This leads you to the wrong idea that your fan is faulty.

Just free up space on top of your case to ensure it’s not responsible for the noise.

5. High CPU Temperatures

When your CPU is overheating, your fan works harder to attain desirable temperatures until it gets to the point of exhaustion.

The more exhausted it gets, the more likely it is to create weird noises.

Before your bother troubleshooting, make sure this is what is triggering your issue by monitoring CPU temperatures.

You can do this either through BIOS or a third-party app.

A. Check CPU Temps In BIOS:

Launch the Start menu and enter the system Settings by hitting the little gear icon at the left.
Select “Update & Security” and then head to the “Recovery” option from the left pane.
Press “Restart Now” under the “Advanced Startup” section.
This will take you to a blue Window, prompting you to “Choose an Option.”
Click “Troubleshoot,” “Advanced Options,” and then UEFI Firmware Settings.
Hit the Restart button, so the computer takes you to the BIOS menu after rebooting.
On the BIOS page, find the hardware monitor section, usually labeled as “H/W Monitor,” “PC Health,” or “Status,” depending on the model.
Temps are shown by either Fahrenheit or Celsius.

Note: CPU temps should be 30 to 40°C when idle and up to 80°C when in use.

Any further results indicate your computer is overheating.

Note that the ideal temperature may also vary due to your CPU model.

Check this chart for more info.

B. Check CPU Temps Via An External Program

There are several temp monitoring tools out there to get a good sense of your CPU and GPU temps.

The advantage they have over your BIOS is that they have a more straightforward interface.

Besides, they’ll warn you if the detected value is too high, so you don’t need to evaluate the temps yourself.

Here are a few examples:

Overheating can have many reasons.

We’ll describe some of them below, including practical solutions to take care of each.

6. Too Many Resource-Intensive Apps

Most often, the resource-heavy programs that run in the background or the foreground stand guilty for an overheating computer.

They overburden your CPU, heat the tower, and therefore, put too much pressure on your ventilation system to cool it off.

Try closing the open tabs on your browser, end unnecessary tasks, and even uninstall some unusable apps to see if the issue disappears.

Here’s how:

Right-click your taskbar (the lower ribbon at the main screen) and open your Task Manager from there.
Under the Processes tab, you’ll see a list of active programs.
Press the CPU section to view the tasks by their usage level.
Then, click the ones with the highest percentage (mostly double-digit numbers) and tap on the “End Task” button at the bottom-right corner.

If it doesn’t seem to solve anything, remove the unwanted applications:

Select the Windows icon at the bottom-left corner of the screen to view the Start menu.
Type “Control Panel” and open what appears in the results.
Go to “Programs” and then “Programs and Features.”
Select the unwanted apps you want to remove, and press “Uninstall.”

7. Malware Infection

If the fan noise isn’t limited to when you’re working with your PC, chances are the problem comes from malware or virus, not a CPU-intensive program.

These intruders consume lots of your processor capacity and storage.

The scenario becomes even worse when it comes to worms because they can spread copies of themselves, eating up all of the resources gradually.

Download and install reliable protection software, ensuring it has anti-malware properties as well.

Then, run a full scan and remove all the malicious executable files or browser extensions it finds as a threat.

Doing so will likely resolve your CPU overheating issue, hence silencing the irksome fan noise.

8. No Breathability

If there’s nothing wrong with the internal apps, your PC temperatures may have heightened due to a blockage in the front of the vents.

Check the ventilation grills for any obstacles such as a piece of paper, cloth, etc.

If you’ve placed the power in a confined area, such as an under-desk cabinet, remove it for a few hours to see if the issue disappears.

If so, find a better place for it.

Anything that obstructs airflow to your computer makes the internal components hot.

This puts more pressure on your fans to cool off the box, making them sound louder and louder.

The same is true with your laptop.

Try not to place it on your legs, bed, or desk without a stand.

It can be anything from a couple of books to a cooling pad.

The latter not only elevates the device to provide airflow but also sucks the heat from your hardware and blows cool air from beneath.

Havit HV-F2056 Laptop Cooler from Amazon is a handy option if you’re considering getting one.

9. Too High Fan Speed

Some computer fans have been set to spin at their maximum capacity while they can’t hold up to that speed or long.

Hence, they indicate the overburden by making wired clatters.

This is mostly the case if you’ve customized your PC for gaming or other CPU-hungry applications.

Fortunately, you can monitor and change your fan speeds using two methods: Your computer’s built-in BIOS and a bunch of third-party apps.

Here’s how to manage your fan settings in the BIOS menu:

Go to your BIOS settings using the same method we mentioned before.
From there, find the hardware management section, which could be named “Monitor,” “Status,” or anything along the same lines, depending on your computer model.
Go to “Fan Speed Control,” locate the RPM settings and turn down the numbers.
Press Enter to apply the changes and the “Esc” button to exit BIOS.

BIOS can only access the fans directly connected to your motherboard. Besides, it may not recognize those fans that are plugged by certain cables and adapters—including 3-pin models.

If the above method didn’t work, adhere to one of the third-party options:

Depending on the manufacturer, each of the apps may function differently, but they all have simple, self-intuitive interfaces.

Just download the latest versions and give them a shot.

Note: For the cooling systems plugged into the power apply, none of the above tricks can work.

You’ll have to buy a noise-emission adapter such as Noctua NA-SRC10, 3 Pin.

It works by restricting the power flowing to your fan and decreasing its spinning.

Fan Speed Controllers such as Noctua NA-FC1 and SCYTHE Kaze Master can also achieve a quieter fan by using the same method.

10. Defective Fan

If none of our fixes helps you get rid of the rattling noise, you have no choice but to accept that it’s dying or at least damaged.

You will need to buy a larger piece of equipment and send it to a repair shop to replace it for you.

If you have a mechanical bone in your body or feel confident DIYing the installation, do the following:

Slide out the side panel to access your unit’s internals.
Locate the computer fan (the one attached to the case shell) and trace its wire to where it comes from. (It’s usually attached to the motherboard.)
Then disconnect the wire.
Unscrew the fan either from the back of the tower or the inside, depending on its model.
This will make the fan loose, so ensure you grab it once you undo all the screws.
Put the new fan in place, re-screw, and reconnect the wires just as you disassembled the previous one.

Video:

Note: Don’t do it yourself if your device is under warranty coverage since it can void it.

Instead, send it to the warranty service and have it repaired for free.

Note 2: Sometimes, your fan isn’t broken but just incapable of cooling your system on its own.

Be it your fault or the fan’s, you can always add another cooling system instead of replacing the old one.

Note 3: This instruction applies to the system fan only while replacing the CPU fan. Other fans may require more technical skills.

We recommend putting it into a qualified technician’s hands.

You can also watch this video to replace a CPU fan:

Video:

Watch this one to replace your graphic card’s fan:

Video:

How To Diagnose The Defective Fan

Before you set out to replace or repair a fan, you need to determine which fan is causing the issue since there’s not just a single fan in your PC tower.

Turn off and plunge your device and use a flashlight to examine the fans for any physical damage such as blade indentation, removal, etc.

Also, try moving the blades by hand to see if they twist with no difficulty.

Alternatively, you can insert a soft, narrow, and long object (like a cardboard tube) between the blades while they’re working to see if the noise lingers.

Then, repeat the process for all the fans to find the culprit.

Don’t use a pencil as many do since it might break the blades.

Plus, make sure not to stick it in the right-angle or counter the rotating direction.

Only do it in the direction of spin.

FAQs On Rattling PC fan

1. Is It Normal To Hear Your Computer Fan?

It’s normal to hear your computer fan unless it makes a very loud sequence of thrumming, clicking, or groaning noises.

Irregular fan whirs, hums, and clunks are usually considered normal.

Yet, if they get on your nerves, you can decrease their speed or replace them with larger, more powerful gear.

Adding a secondary cooling system can also make a difference.

2. What Does A Bad Computer Fan Sound Like?

A bad computer fan sounds like a bike wheel that spins while inserting a pencil between its spokes.

It’s a loud, quick, and unsteady burst of ticking sounds that repeats on the trot.

If what you’re hearing is more like the Batmobile’s turbine sound, chances are it’s just blasting with the max rpm to dispel excess heat.

After all, fans circulate air, and air produces sound waves.

Groaning sounds from your fan will also indicate a clump of hair or other particles have stuck between the blades, not a broken fan.

3. Is A Rattling PC Fan Bad?

A rattling PC fan is bad; so is one that is scratching or grinding, especially if they tend to become louder after a while.

However, if the sound only kicks in while playing games, editing videos, or doing other CPU-hungry tasks, all you need is to find a way to reduce the CPU temperatures.

4. How Do I Fix The Fan Noise On My Computer?

Fix the fan noise on your computer using the following simple steps:

Move your unit to an even surface without anything hindering its vents.
Make sure the fan is securely attached to its place and with a quality fan grommet.
Clean the vents, blades, and everything related to your fans.
Force stop the CPU-consuming, unwanted apps.
Reduce your fan’s RPM numbers using SpeedFan utility.
Remove viruses, worms, and spyware.
Install an assisting cooling item.