How to Check Power Supply on PC Windows 10?

A power supply unit, or PSU, is a critical computer component that converts AC (alternating current) from your power supply outlet to DC (direct current), which is needed to power your CPU, motherboard, and other computer components.

The PSU is typically located in a box located on the floor or elsewhere near your power outlet and also usually houses the fan. In this guide, I will show you how to check your PSU and ensure it is working properly.

Why Your Power Supply Matters

Your PSU ensures your computer components can get power. A faulty PSU can lead to various issues, mainly your computer not turning on or components failing.

Knowing how to test for power supply problems on a PC is important. If you are experiencing PC failure symptoms, you need to know how to isolate the issue. By testing your PSU, you can check if the PSU is the issue or if there may be another component that is faulty.

In this guide, I will show you how to troubleshoot and test your PSU.

Safety First: What to Do Before Testing a PSU

Before testing the PSU, it’s important to be sure that you are not doing any work, including connecting or disconnecting wires, while the PSU is actually turned on.

While you need the PSU to be plugged into your power outlet to test if it’s receiving power properly, make sure it’s not turned on when connecting or disconnecting wires. Make sure it’s not resting on a conductive surface when testing.

Take the power supply unit out of the large computer case before testing. While it’s not required, it might make it easier for you to isolate it from other components.

How to Test if Your Power Supply Turns On (Paperclip Test)

When using the paperclip test, connect the green PS-ON pin to a black Ground pin, but never connect two pins of the same color.

The first test you can do, even without extra equipment, is the paperclip test. The paperclip test for a PSU is a simple test that checks if a PSU turns on when you simulate a PC connection with a paperclip.

This tests if a power supply and its fan are working. If it fails the paperclip test, you have correctly identified the PSU as faulty. That means that you need to replace the PSU.

To perform the paper clip test, first turn off the PSU and make sure the PSU is out of its large box (but don’t open the actual PSU unit itself).

Unplug all the wires from the PSU except for the 24-clip connector which connects it to the motherboard. Disconnect the motherboard, but leave the other end of the connector connected to the PSU.

Locate two pins. One of them should be green (PS-ON) while the other should be black (ground). These are typically pin #16 and pin #17 on a 24-pin connector.

Take a paperclip and bend it into a U shape. Insert one end into a green pin and one end into a black pin. Important: The PSU should not be turned on when inserting the paperclip! For added security, disconnect it from the power source while inserting the paper clip.

Also, never put the two ends of the paper clip into two pins of the same color.

Before proceeding, make sure the PSU’s Eco Mode is not turned on, if it does have an Eco Mode.

Once the paper clip is securely inserted, turn the PSU on. If the fan turns on, that indicates that the PSU is operating. If it doesn’t turn on, it means it is not working properly.

However, even if it turns on, it doesn’t show you how much voltage it has or if it’s the correct wattage. Thus, the paper clip test is a very rudimentary test. If you want to make sure the PSU has no problems at all, it’s best to use a PSU tester.

How to Test Your Power Supply With a PSU Tester

A PSU tester tool is much better for testing your power supply and its voltage than a paper clip. A paper clip only tells you if the PSU turns on, but it may still have the incorrect voltage and may still be faulty when powering on your PC.

PSU tester tools are available on Amazon. They connect directly to the 24-pin connector that typically connects to the motherboard and have indicators (or a digital screen) that tell you if the voltages are correct. You just have to connect it to the 24-pin connector, turn on the PSU, and check the readings or ensure the indicator lights are green.

One important thing to note is that these typically still do not test your PSU under full load.

How to Check Power Supply Wattage Without Opening the PC

You can check the PSU’s wattage and other specs by looking at the sticker on the PSU case or checking the model’s specs online, if you know the model name or number. You can typically find these specs on the manufacturer’s and/or third-party websites.

Unfortunately, there is no software tool that can tell you if your PSU is working properly or how much voltage it has.

How to Check Power Usage in Windows 10

Unfortunately, there is no software that can tell you how much voltage the PSU is outputting or if it’s meeting its designed capacity. That’s because of the way the PSU interacts with your computer. It provides power to the computer components but does not interact directly with the operating system.

Therefore, any software tool can only tell you how much voltage your computer is receiving from the PSU, but this does not tell you anything about the health of the PSU itself. For example, HWiNFO can provide details about your motherboard’s voltage rails, but this still doesn’t tell you everything about the PSU itself.

Another tool, OCCT (OverClock Checking Tool), allows you to stress test your system by putting a lot of stress on your PSU and checking if it can hold up. However, it doesn’t provide precise measurements as to the PSU’s health.

Signs Your Power Supply Is Failing or Not Powerful Enough

Signs of a failing power supply unit include:

Random shutdowns
Boot failures
Unexpected reboots
Blue screen of death
Clicking, buzzing, or other strange noises coming from the PSU or its fan
Overheating

These often indicate that your power supply is not powerful enough, especially if the shutdowns and other issues occur during gaming or when the computer system is otherwise under heavy stress.

When You Should Replace Your Power Supply

So, when is it time to replace a power supply? You should typically replace a PSU if you are experiencing any of the issues mentioned in the previous section and have confirmed that the PSU is the issue.

If you are experiencing random shutdowns, for example, use a PSU tester to check the PSU strength.

You should upgrade your PC power supply if it doesn’t have enough power to meet your needs or if it’s old or failing. If you are hearing strange noises from the PSU, or if you smell a burning smell indicating an electrical malfunction, replace the PSU immediately.

Conclusion

Testing a PSU isn’t rocket science, but it does require a bit of technical know-how. You will need to use a PSU tester or, if you don’t have one, a paper clip while ensuring you are staying safe. Unfortunately, you can only test the PSU by handling the unit directly, as there’s no software on Windows that can do this for you.