Why is My PSU Fan Not Spinning? Hints and Solutions

If you’re having trouble with your PSU fan not spinning, I know how frustrating it can be, especially as a PSU fan is essential for any computer that has a power supply.

Truth is, a malfunctioning fan can cause your pc to overheat and damage the motherboard, which is why it’s important to troubleshoot as soon as you start noticing problems.

The good news is that there are a few known common reasons for this. In this article, we will go through the most common ways to fix a PSU that has stopped spinning.

Why Is My PSU Fan Not Spinning?

The most common reason for a PSU to stop spinning is due to overheating from dust build-up.

Another possible cause for this may be that an internal circuit has broken and needs replacement via soldering skills. We will now dive deeper into the main reasons why PSU fans break and stop spinning.

Semi-Passive Cooling Mode

The first thing to do is check the power-supply’s manual to see if it offers a semi-passive cooling mode. This function will reduce the spinning speed of the fan when fewer load is put on it, which could considerably improve your PSU’s lifespan.

This basically means that your PSU fan isn’t spinning because it simply doesn’t need to. If you’re using your PC for light tasks, then it’s likely that there’s a semi-passive cooling function, and you have nothing to worry about. However, if the fan isn’t spinning even while under heavy demand, then something has gone wrong. For context, the semi-passive cooling mode may cause the fan to start working from 15% – 40% PSU load – it will vary depending on the manufacturer.


If dust has been building up inside your device for some time, then this can block airflow and overheat components. If there are no vents on the back or top of your PC, then a fan may not be able to properly pull in air. This can result in overheating and damage during prolonged use.

You can get rid of dust in a fan by using a can of compressed air (or an electronic vacuum cleaner) to blow the dust out. You can also use canned air and cotton swabs dipped in rubbing alcohol to remove stubborn particles.

Loose Connections

Make sure there hasn’t been any physical damage to the power cable, or any loose connections where the PSU fan plugs in.

Misaligned Fan

If you can hear a grinding sound coming from your fan when it tries to spin, then this means one of its blades may have become bent. If not, there’s a chance that they’ve simply come away from their fastenings altogether, which is more difficult but still fixable. Try undoing all screws on both sides until you get down to the actual assembly level.

Overheated Components

This problem usually happens because something inside has been so badly damaged by heat that it went into thermal runaway mode without warning – and now you need either professional help or a new replacement.

Disconnected Power Supply Unit

It may sound silly, but check if the power supply is actually connected.


Your PSU’s fan won’t be able to spin if something is blocking its path – check for any wires that might have been pushed down too far, preventing airflow. For example, an HDMI cable could easily block a case fan from spinning while it’s plugged into the motherboard. The same goes for power cables near the CPU cooler as well!

PSU Fan Still Not Working?

If your PSU fan is still not working, the best case may just be to get a new one. You should be able to clean the dust from your PSU fan, but sometimes the debris will have made the fan permanently faulty.

Luckily, it’s fairly easy to find a PSU fan for your PC. I recommend using a PSU fan with great static pressure (Amazon link), as this will give the best performance in terms of cooling.

Please note: Changing your PSU fan means opening up your PC. You should always make sure that there is no charge left in your PC when fitting and removing components.


In conclusion, the most common reasons why fans stop working is due to dust build-up, which can easily be removed with compressed air or vacuum cleaners.

It’s also important to consider that many PSU fans have a semi-passive cooling mode, which means that they will only start spinning when the PSU reaches a certain temperature. If your fan is not spinning, it’s possible that your PC just may not need to be cooled down yet.

I hope you have enjoyed reading this article. Please do not hesitate to ask me any questions in the comments section below or contact us.