How To Diagnose And Fix A PSU Overheating

If your PSU is overheating, it potentially has a negative impact on any component that it powers. I advise resolving this issue urgently before damage is incurred to other parts of your computer.

An overheating power supply unit (PSU) in desktop computers is usually a result of a build-up of dust in it, preventing proper cooling. Other causes are an underpowered PSU, PC airflow configuration, or it’s getting old.

Unfortunately, an overheating PSU is one of the riskiest kinds of problems to have with computer hardware.

The reason is that every component that gets powered from the PSU inside your computer case needs a good quality power source to work correctly.

If you have power supply issues, components can risk malfunctioning or overheating themselves.

Not to mention that an overheating PSU can raise the internal temperature of your computer depending on the PC airflow configuration.

Other symptoms could include freezing, random restarts, display glitches, random shutdowns, micro stuttering, or not starting up after restarting.

Let’s dive deeper to see what else we can point out to help you fix the problem.

Resolve PSU Overheating by Using These Steps

Here I have compiled a list of issues with the fix to help you understand what’s causing your PSU to overheat.

Clean the inside of your computer

In case you’ve noticed, I didn’t only mention cleaning your PSU. You must clean it, yes, but a clean computer will help lower the internal temperature of your computer in general.

Unplug your computer from power, disconnect all the power cables inside your system, unscrew it, and remove it altogether to clean it properly.

It is sometimes challenging to clean a PSU inside a computer case, as there are many obstructions for you to gain access to it for a proper clean.

The best way to clean all the components effectively is by using a small brush and compressed air.

Caution! Do not open the PSU itself unless you are a qualified repair technician.

Clean the PSU by blowing compressed air through it. It is best to use a proper air compressor. Ask a neighbor or a repair center to blow it out for you if you are out of options.

If all else fails, purchase a can of compressed air or a small battery-powered duster.

Note: I highly recommend that you wear some sort of face covering and something to protect your eyes.

Your PSU may be underpowered for your system

This shouldn’t be one of those situations where your power supply is suddenly getting hot.

It can worsen as the PSU ages, but generally, it would have been getting hot from day one.

Check your system’s requirements, and ensure you have a power supply matched accordingly.

I usually like to get a PSU with a bit of extra power above what’s required to ensure that the PSU stays cool and works with less strain.

It will usually result in a longer-lasting PSU and allow some extra flexibility if you upgrade components that require more power later.

I have written an article all about knowing whether or not you need a new power supply if you’d like more information.

Check the airflow configuration inside your computer case

Recently, manufacturers have decided that the PSU should draw air in from outside the case directly instead of inside the computer.

Older case designs had PSUs draw air in from inside your computer case. The system’s internal temperature had to be low enough for the PSU to provide proper cooling, which was difficult.

This design was terrible. Using warmer air inside a PC case wouldn’t result in very efficient cooling.

The overspill of heat from the PSU could cause even further heat inside the computer case.

It’s especially important if your PSU uses your computer’s internal air to cool that you have adequate cooling inside your case.

You must ensure plenty of air is taken in and moved out consistently.

Your power supply has done its time

An aging power supply is another reason for PSU overheating. As it ages, it becomes less efficient and generates more heat from its internal components.

With this, lowered expectations of a PSU meeting its specifications become evident.

There are excellent power supplies made by manufacturers like Seasonic that offer a ten-year warranty, but for the other PSUs on the market, you’d want to look at replacing them after around five years.

A component is causing an abnormal load

In less common situations, a component, like a motherboard, can have a failing SMD component that causes an abnormal load just enough not to send your PSU into protection.

It can draw more current than usual, thus taking up more power from your PSU than it usually would.

PSUs generally have effective protection mechanisms that detect abnormal loads and shut themselves off to prevent damage.

However, in some rare cases, a faulty component or semiconductor can cause extra power use and generate more heat. For example, faulty regulators.

It may be harder to detect because everything can function perfectly normally for some time before the problem becomes more apparent.

Check all connectors are pressed in properly

This has a lesser chance of a cause for PSU overheating, but worth a check over, not just for this problem.

Go through your entire system, everywhere a connector is associated with the PSU, and make sure everything is firmly pressed into place.

Look for small gaps between connectors that indicate something isn’t seated fully.

Make sure the PSU fan is working

With many PSUs, the fan usually only starts spinning when sufficient heat is generated from the PSU.

To test it, watch for fan rotation when the PSU heats up.

If it doesn’t spin up or spins up too slowly for the generated heat, something is wrong with the fan or the controller that determines its speed.

Some PSUs can work with software that provides you with specific diagnostics, fan speed, and temperature reporting in real time.

This can be very handy and greatly cut the diagnosing time.

Make sure the room temperature isn’t too high

This is true for all computer components in general. But for this article, we will focus on the PSU.

Higher ambient temperatures in a room can significantly increase your PSU’s temperature.

This becomes even more emphasized when you live in a high-humidity climate.

It becomes way more difficult for fans to keep components or heatsinks cool under these conditions.

In this case, try to move your computer to a cooler room, install an air conditioner, or look at other ways to reduce the heat in the room.

Check the case fan speed profiles and your BIOS

To eliminate other components in your system overheating, we must ensure your fans are doing their job.

It could be affecting your PSU temperature somehow, so it’s a good idea to ensure that your PC’s internal temperature is reasonable.

Some computer case fans rely on the BIOS to setup up the fan temperature speed curve. If something isn’t adequately set, try resetting your BIOS to optimum defaults.

If the fans aren’t spinning up as they should, go back into the BIOS and adjust the fan speed settings until you are satisfied.

If your case fans are controlled by software in your operating system, ensure the temperature speed profiles are adequate.

And unfortunately, if you live in a hotter climate, fans will make a bit of noise when your computer works harder.

When all else fails, replace the PSU

Sometimes a PSU can overheat, even when all these checks have been done and no fault is found.

In this case, try and get an RMA for a return, or spend the money and replace it with a new one.

I don’t recommend purchasing a second power supply, as it’s one of those parts inside your machine that is so crucial and warrants a brand-new replacement.

If you look at the worst-case scenario, you’ll have a spare PSU if it doesn’t fix it.

This isn’t a bad thing. A faulty PSU causes your whole system to be out of action, and it isn’t silly to have a spare.

It is also useful for other checks in the future when diagnosing other computer faults. For example, power supplies can cause problems that might be hard to diagnose with a spare.

For laptops

I thought it only fair to run over some examples causing overheating PSUs for laptops too.

• Check that you have the correct PSU adapter for your machine.
• Check that your battery is charging as it should. If it takes a long time to charge or runs down quickly, you may put an extra load on the PSU adapter and need to replace the laptop’s battery.
• Ensure the PSU adapter isn’t sitting in the sun or near something hot.
• Check the cables for damage. If there’s any damage, get the PSU adapter replaced immediately.
• Check that the PSU power adapter plug fits snugly into the laptop’s socket.
• Clean the laptop’s inside and ensure the cooling system is dust-free.
• If it’s old, look at replacing it.

Conclusion

There you have the top reasons for an overheating PSU. I hope it gave you the information you need to get it fixed.

Please don’t leave the situation unresolved. Get your power supply back to normal temperatures before you resume regularly using your machine.

Once you have dealt with it, you will have a safer, cooler, and quieter computer.