How to Tell If CPU Fan is Broken [Signs, Reasons & Fixes]

Written By Steven Arends

Do you know that your CPU cooling fan may stop functioning, just as RAM and Hard drives can?

A broken fan is harmful to the processor and can cause several issues in the

The problem is that many users don’t know how to tell if the CPU fan is failing.

Don’t worry, here I will describe some tested and proven ways that will help you know whether your CPU fan is working.

So, tag along.

How to Know If CPU Fan is Broken

Visually checking the CPU fan is the best way to determine whether it’s broken. Open the case and look at the fan. If you see the fan is not rotating, it means it isn’t working. Also, unusual fan movement and spinning sound indicate the cooling fan is faulty.

Besides, checking physically, you can perceive your processor fan is not working by noticing some signs. Looking at those signs, you can check if the desktops and the laptop’s CPU fan are operating.

Check out those signs

Here are the symptoms to find out whether a CPU fan is failing:

No Spinning Sound

Not hearing any sound will be your first sign that your cooling fan is broken.

While the fan is working, a light humming sound will always come from your desktop or laptop computer. If there isn’t any, it means the fan is dead.

Abnormal Noises from the Fan

Unusual or loud noise from the CPU fan should be your second sign to know the fan is broken.

A low-level whizzing sound you should hear while the fan is healthy. Whether the fan is moving, but the sound seems odd to you, it only means your PC is experiencing a CPU fan error.

You may read our other guide to know why your cooler is making loud noise.

Bad Smell is Coming Out

Your nose can be a great ally to detect a broken CPU fan.

If the fan is damaged due to burning, a flaming stink will come out of your PC. When you get some kind of burning smell, you can know your heatsink is defective.

Too Hot or Overheat Issue

The primary purpose of a CPU fan is to keep the processor cool. When your processor and PC are becoming too hot and excessive hot air is coming out through the PC vents, it can only mean the fan is not performing well.

Check the CPU temperature and if it’s overheating, this can be due to a faulty or broken fan.

Random Shut Down, Freeze, and BSOD Happen

All modern CPUs have a built-in thermal protection system. When the PC gets overheated, it shuts down.

If your PC is frequently getting warmer right after you start the computer and take a random shutdown or freeze out of nowhere, it indicates that your CPU fan is faulty.

Also, a sudden BSOD appearance due to overheating indicates your fan is not working. For additional information, see the article: how to tell if a CPU cooler is bad.

What Causes the CPU Fan to Stop Working?


Dust is the main culprit that stops the CPU fans from functioning. Besides dust, rusty bearings, malfunction of the fan header, incorrect fan installation, sudden power disruption, faulty fan cable, and CPU overheating can also cause the fan to break down.

Dust is the one thing you will find in every corner of the world. So, you shouldn’t be surprised if you see dust stored inside your PC case and in your CPU cooling fan.

When too much dust is stored up, and you don’t clean that dust from time to time, the fan’s efficiency starts to reduce. And at some point, it stops working.

Modern CPU fans have bearings that help reduce friction between rotating and moving parts. It provides the fan to operate smoothly.

But over time, the fan’s bearing starts to degrade. And this degradation of bearings causes the fan to stop working.

Most users don’t provide their PC proper air ventilation. That’s why the air filter blocks and the computer overheats. Due to overheating, the processor’s cooling system can break down.

Overheating also causes a failing thermal paste issue, which is bad news for a cooling fan.

Additionally, if the fan connection is loose and a sudden power fluctuation happens from the power supply unit, it can damage the fan cable, and the fan may stop working.

What Will Happen If a CPU Fan Fails?

If the CPU fan fails and stops working, the PC will automatically shut off after a few moments. The processor will damage due to overheating without a working cooling fan. This damaged CPU can also destroy other important hardware components like the motherboard.

It’s a terrible state for a PC when the CPU fan stops functioning.

A dead heatsink will cause a lot of issues in the PC. Most of the time, the PC won’t turn on. Even if it boots up, the PC will shut down completely to save the processor from getting damaged from overheating.

This overheating and sudden shutdown reduce the processor’s lifespan and cause corruption of files, data loss, throttling, show BSOD (Blue Screen of Death), and system failures.

If you are worried about your CPU, check our separate guide on how to tell if the CPU is failing or dead.

How to Prevent the CPU Fan from Getting Damaged

Cleaning the CPU fan should be your first step if you want to save your CPU fan from failing. Also, keep the PC in a place that is a dust-free zone and has a space for proper airflow. Additionally, stop overclocking and include adequate cooling if necessary.

To clean the CPU fan, use a small-headed brush and microfiber cloth. Do the cleaning every six months. This way, dust won’t be able to stop the fan from working.

You must avoid overclocking as much as possible to keep your cooling fan and processor well-maintained.

Besides, if one cooling fan is not enough to cool down the CPU heat, add an extra cooling fan. It will help reduce the load on your CPU fan and prevent it from damaging.

You should replace the fan if it becomes too noisy. When you place a new heatsink on the processor, ensure you get a better one and set it appropriately.

Check out our expert’s opinion about whether it is worth getting an expensive CPU cooler.

Note: Don’t use your computer as long as you don’t replace your broken CPU fan.


Why did my CPU fan suddenly stop working?

When too much dust builds in the CPU fans and gets clogged up, the CPU fans stop working.

What is the lifespan of a PC fan?

A desktop computer fan can last up to 5 to 6 years on average. On the other hand, a laptop fan can give service for close to 9 to 10 years.

How long can a PC run without a CPU fan?

The processor heats up fast. Since most computers have a built-in thermal protection system, the PC can run for about 25 to 30 seconds without a fan.

Ending Remarks

It’s nearly impossible to repair a broken cooling fan. It will be a wise idea to get a better cooling fan. Take help from a PC expert if you have no idea which cooling fan will be better for your PC and how to attach it to the top of the processor.

I hope you won’t have any problem further detecting any broken CPU fan. Comment below if you have any queries.

Peace out!

About The Author
Steven Arends is a computer science graduate and tech enthusiast with over 10 years of experience in the field. He has a vast collection of computer hardware and loves exploring the latest advancements. As a contributing author to 10Scopes, Steven shares his expertise to make the world of technology more accessible and easier to understand for all readers.

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