How To Know If You Need A New Power Supply

A properly functioning power supply is the most crucial part of any PC. PSU problems can be detrimental and very expensive, depending on your rig. Not to mention other annoying faults that may crop up from time to time.

Here are 7 ways to know if you need a new power supply:
  1. Age.
  2. Programs crash without corresponding software issues. 
  3. You experience random blue screen crashes.
  4. You hear unknown PC case noises.
  5. Fans turn on, but nothing else.
  6. GPU-intensive programs start having issues. 
  7. You notice visual power fluctuations.
  8. Running multiple devices yields poor performance.
  9. It has swollen electrolytic capacitors.

Faulty power supplies can cause problems, and it’s sometimes difficult to narrow things down too much without the proper test equipment.

Note: I would like to point out that the proper way to test a power supply is by using a tester with a dummy load. Since this equipment is not usually used by everyday computer owners, this article is about trying to find an answer without using the proper test equipment.

How to Know if You Need a New Power Supply

So here are a few things to look out for to diagnose whether or not it’s time for a power supply change.

Replacing your power supply or seeing malfunctions with your PC can be worrying, but read on for easy ways to tell what shape it’s in.

How to know if you need a new power supply.

1. Age

This is probably one of the more conclusive ways to determine whether your power needs replacing.

Power supplies generally last around five years, except some manufacturers make more durable supplies with warranties spanning ten years or more.

If your power supply exceeds the five-year age, it’s most likely time to replace it. Providing your computer’s components with good quality power ensures longer life and better performance.

This is especially true if the power supply in question is of the cheaper variety. But unfortunately, there are many cheaper ones out there that I encourage people never to use in the first place.

2. Programs crash without software issues 

Computer error with a concerned woman staring at the screen.

If programs randomly crash without a corresponding software issue, it can signify that your power supply isn’t strong enough to run them.

Check the code integrity of your programs. If you don’t see any flaws or issues, check other troubleshooting.

Sometimes, there are new updates that need to be installed. Other times, programs aren’t suited for modern computers and need help with modern operating systems and graphics cards.

Make sure to look in program forums for any issues that could mimic what you’re experiencing. Many people who post in forums are programmers or enthusiasts who know more about PCs than the average person.

You should check your power supply if you can’t find reasons for your computer’s issues.

Sometimes, programs crash due to system instabilities caused by the power supply when the computer experiences a heavier workload.

3. You experience random blue screen crashes

A Windows Blue Screen error (BSoD).

If you’re experiencing random blue screen crashes without explanation, you may have power supply issues. 

Verify that the blue screen crashes are not from your activities. Sometimes, users can cause issues with their operating system by accidentally getting into something in the base code. 

Occasionally, programs can work poorly together and cause problems.

Sometimes, operating systems have issues that happen during common runtime. However, this is less common unless you haven’t regularly updated your device or have contracted a computer virus.

Check forums to see if there’s any explanation other than power supply issues. As with the crash issues, many computer experts could be able to help.

It may be worth checking your power supply if you don’t find anything.

Blue screen crashes usually mean something is happening with the primary operating system. Sometimes, power fluctuations can cause the OS to have issues.

So, in this case, the computer is failing to keep your components running correctly.

4. You hear unknown PC case noises

Sometimes, unknown noises mean something has come loose or is having issues.

When you hear an odd noise, check all your devices. It could also be good to take apart specific devices and examine their parts if you can or have the know-how.

However, don’t take apart your power supply; you could seriously hurt yourself.

A high-pitched hiss or whine could be caused by electromagnetic interference from power strips or lights. Move your power supply away from the interference and see if the problem persists. 

If the noise continues, you may have faulty internal components and need to replace your power supply.

Unplug your power supply and leave it alone until you can replace it.

5. The fans turns on, but nothing else

If your fans are the only devices turning on, your power supply may have connectivity issues or cannot provide enough power to your setup. This creates a domino effect throughout your PC.

Make sure that all the wires are correctly connected and aren’t damaged. Check for any sorts of issues, like exposed wires or cracks.

Devices under high stress might manifest problems they didn’t have before. Likewise, vibrations or rubbing up against case walls can wear down your devices during regular use.

This is the most common sign that power isn’t transferred to all devices within your PC.

However, it can indicate other issues, so it’s best to check various components before confirming the power supply.

Sometimes, issues with other parts can make the power supply function differently than it normally should.

If they’re dependent on the power supply, they can introduce issues anywhere between the supply and components themselves.

6. GPU-intensive programs don’t start or run

A wireframe CAD model of a graphics card.

GPU-intensive games or programs can also indicate that your power supply is having issues. If they struggle to start up or run consistently, that’s a good sign that you have an inadequate power setup. 

Close all programs using the Task Manager to test if this is the cause. Then, open and run a game or program that subjects the GPU to a heavy workload.

This can be anything from video games to mapping programs. Anything that could put your PC under stress could help.

Your computer’s performance will suffer if devices aren’t being appropriately powered. This is the best way to check and see if you need a new or upgraded power supply.

It’ll quickly determine the issue and be much easier to fix than a wiring issue.

If you see a significant decrease, it can be related. Your power supply could be struggling to keep up, and your graphics card could start to operate abnormally, run hotter, or drop frames.

For this test, it may be worth mentioning that your graphics card could be the reason for the malfunctions, so I recommend you test it to see if it’s the culprit.

7. You notice visual power fluctuations

Sometimes, issues with a power supply can manifest visually to the naked eye. This can be easy to spot and be your first clue that something isn’t right.

If you have lights in your PC case and can see them flickering, it’s a tell-tale sign that your power supply is having issues or is inadequate for your setup.

Lights are susceptible to power fluctuations and can be an easy place to start looking for problems. 

Have you ever been in a home where the lights flicker when the air conditioner turns on? That’s because the voltage drops when major appliances pull away from the main power supply.

The same effect can happen with your PC.

You can also look at other lights on your device. For example, if you have strip LEDs in your PC case, those can also show signs of electronic stress.

Verify the integrity of the wiring, and then check your power supply.

8. Running multiple devices yields poor performance

Running multiple devices from the same power supply can put extra stress on it and slow down performance. 

First, ensure your power supply is rated for your connected devices. If they aren’t, you need to upgrade it.

You may get external USB devices not being recognized. Just make sure that it isn’t a USB cable that’s inadequate before condemning the power supply.

9. Swollen or leaking electrolytic capacitors

Swollen and leaky electrolytic capacitors.

Looking at some internal electronic components, specifically the capacitors, is an easy tell-tale sign that your power supply is past its due date.

Once the capacitors age, they start bulging, and the most obvious place to see this is on the top of a capacitor.

The top of the capacitor will protrude convexly, giving the appearance of a small dome.

In some cases, it won’t be easy to see through the vent holes of the power supply. Therefore, I do NOT encourage you to open the power supply and take a look.

Some large capacitors hold many electrical charges that can give you an uncomfortable shock or worse.

If you cannot see inside, I’d advise you to skip this step.

How to know if you need to upgrade your power supply

There are a couple of ways to know you need to upgrade your power supply.

Testing a computer power supply using a multimeter.

Upgrades were done on the PC

If you have recently upgraded other computer parts, you could need a new supply to support them and the rest of your PC.

Wattage too low 

You must check the power supply compared to each component’s wattage requirements. If the power supply’s total wattage falls short, upgrade it immediately.

Inadequate wattage can be dangerous and impact your overall performance.

Running devices with a lower power supply or lower wattage tolerance can be dangerous and a safety hazard. In addition, increased temperatures can melt wire coatings and potentially melt other parts or cause a fire.

Once you’ve verified if you need to upgrade your power supply, turn your computer off and wait for a suitable replacement.

Important: I don’t recommend using the computer until you are able to get a new power supply installed.

I have written more on this topic in my article answering how many Watts should a gaming PC have.

Choosing the right power supply for you

Make sure to research the power supply you want to upgrade to. It would be best to verify that it’s from a reputable dealer. If you don’t, you risk running into problems later on.

While snatching up a cheap deal on a power supply can be tempting, ensure you know what you’re purchasing.

The lowered cost can come with potential issues in the future. They can even cause safety problems.  

Choosing a suitable power supply is a more complicated question. It would be best if you considered your current setup before anything else. You can also select based on three options: 


Another thing to consider is the price of the power supply. Sometimes, there are terrific deals on power supplies out there.

For example, many companies will have discounts when you buy power supplies with other PC parts, or they might offer special sales for holidays.

However, like most things in the tech world, you get what you pay for. Therefore, if you go for a good deal, you may encounter specific issues with the quality and the materials used to build your power supply.

It can be better to spend more money now than pay dearly down the road with damages. Good quality power supplies don’t cost a whole lot more anyway.

It may simply mean paying an extra 50 to 80 Dollars, not exactly enough to break the bank. However, it’s money well spent knowing that your computer is getting reliable and good-quality power.

Future builds

It would help to consider using your power supply for newer builds.

If you grandfather various PC parts with future upgrades, you should choose a more modern power supply with a higher wattage rating.

This will allow it to handle future parts requiring a higher power level and prevent your power supply from needing replacement once again.


The wattage value of your power supply determines how much power it can deliver based on the need for the sum of all the components in your computer.

If it’s too low, the power supply will run hotter as it cannot keep up with the demands of your system’s components.

You can always go much higher than required. Simply a waste of money. So the idea is to have a little headroom and call it a day.

Always remember that the power supply unit needs to match the form factor of your computer’s case.

So before purchasing that slightly larger power supply, ensure it will fit and mount correctly.

Proper ways to test a power supply

As I mentioned at the beginning of the article, there are proper tests that can give you a better insight into the condition of your power supply.

Method 1:

One way is to purchase a power supply tester.

This is great for an initial test, but it doesn’t subject a power supply to the load it would have when powering a computer with a graphics card.

Method 2:

Professionals use elaborate test equipment that isn’t commonly found in stores. These testers can perform a detailed analysis of all the power rails generated by the power supply while applying a load amount of the tester’s choice.

An example of one of these testers is the Sunmoon SM-5500ATE.

Seeing as it’s unlikely for most people to own equipment like this for themselves, DIY’ers have been putting together their dummy load circuits and using a multimeter to test each voltage output.

This is cruder but can be somewhat effective. The only genuine test is to apply a great enough load on the power supply while measuring it over a certain period.


That covers some common symptoms and telltale signs that your power supply needs replacing.

I’ve encountered other symptoms less commonly experienced from a faulty power supply while repairing computers.

Some of these include:

  • Unexpected restarts.
  • Black screen of death.
  • Random freezing.
  • The internal temperature of the computer rises above normal.
  • CPU and/or GPU run hotter than usual.
  • Micro stutters.
  • Several attempts to get the computer to start up. Usually, pressing the power button a few times over about ten minutes.
  • Increased power use.

Considering how important power supplies are in a computer, keeping one spare for your system is not stupid.

It can also be a great way to eliminate power supply problems if you aren’t entirely sure which hardware component is the cause of your issues.

This is largely true because everything relies on power to work. Therefore, the power quality can determine how well or reliably every component works.