How to check the computer power supply? (Brief Guide)
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For a computer to function, it must have a power supply unit. You can decide if your system has the optimal configuration for your computer or gaming needs by knowing the precise specifications of your PSU. Find a simple technique for How to check computer power supply here! This article looks at many methods for determining what PSU you have.
For your PSU’s test:
- Turn off your PSU
- Disconnect all cables from the PSU besides the 24-pin cable and the main AC cable.
- Find pins 4 and 5 on the 24-pin wire.
- Bend your paper clip, so the ends fit into pins 4 and 5.
- Start the PSU
Check to see if the PSU fan spins.

How to check the computer power supply
Check The PSU Physically:
You should know the PSU’s specifications if you constructed your computer and it wasn’t purchased pre-made. However, if it’s a pre-built PC, you might not know your power supply. Because its only function is to provide power to the computer components, power supplies don’t interface with motherboards.
There is no method to find out what PSU you have through your computer’s interface. Physically inspecting your power source is the simplest approach to determine it.

Depending on the manufacturer, each PC offers information about the PSU within the chassis in a different area. The PSU will be located with a label or sticker on the side or at the top that lists all the information about the PSU after you open the side panel of the computer case.
The power supply could be installed in a different case within the computer that you have to unscrew, depending on the model and manufacturer. You must then remove the PSU shrouding box. This is how you do it:
Please turn off the computer’s power before unplugging all its wires, including the power cord and other accessories. Based on the work and manufacturer, you should either unclip or unscrew the side panel to open the case.
The power supply is simple to locate, typically close to the port for the power cord. If you can’t see it, it must be on the side of the PSU that isn’t visible.
All power supplies are required to have this sticker showing their specifications. It’s not a trusted brand if there isn’t a sticker or label on any side because Underwriters Laboratories requires all manufacturers to offer this information. As a result, you might want to replace your power supply before it harms your computer.
Online Search:
This method is valid if you have a pre-built PC but don’t want to open your case. You can visit the manufacturer’s website, type in your PC’s model number, and search for the PSU specifications. The best option is to open the case and physically inspect the PSU because manufacturers occasionally alter its specifications and features for future iterations of the same model.
But not all manufacturers offer this information, so you might not discover it on some of their official websites. It also helps to Google the make and model of your PC and look up the power supply’s specifications on reputable sources. You can learn what PSU you have with the assistance of devoted and informed members of online forums.
User Manual:
If you have a pre-built computer, you can check the user guide to see what kind of power supply you have. The manufacturer provides a complete list of specifications. If it doesn’t, you can check the PSU’s model number and use it to conduct a web search for further information.
Why Do You Need To Know What Power Supply You Have?
Your computer’s power supply is important and can impact the overall performance and operation of each component. This is because it supplies electricity to each component according to their needs. Additionally, it converts the AC electricity into a low voltage DC usable by computer components.
You might never need to know about the characteristics of your power supply if you’re content with your present PC and don’t want to make any modifications or if you’re not that tech-savvy.

However, understanding your power supply is important if you wish to upgrade your components or overclock your system. Imagine you want to upgrade your PC’s GPU to make it a gaming setup. In that situation, you must determine whether your power supply can provide the GPU with adequate power to operate effectively and to its full potential.
You risk damaging the components if you don’t utilize an appropriate PSU because you won’t be providing them with enough power. The PSU’s wattage is the most crucial element. The combined wattage of the PSU should not exceed the power needs of any PC component.
Otherwise, the PSU will malfunction, or your computer may shut off. You can make the best possible component selections by being aware of your PSU’s limitations. You can also look for a stronger power supply compatible with new components if you’re in the market for improvements. Knowing the maximum load on your power supply is necessary if you wish to improve.
What about the components? How can you prevent the PSU from being overloaded by the new components and burning? As a general rule, add 150W to ensure every component gets enough power after determining your total power requirement. However, determining the size you want for a power supply can be difficult.
How to Choose the Best PSU?
Now that you know the PSU size you require, you should consider a few additional characteristics.
Custom vs. Standard PSUs:
Two terms may come up regularly when looking for a power supply: bespoke and standard PSUs. Companies like Cooler Master and Corsair make standard PSUs specifically for gaming. These power supplies weigh a lot and have premium parts and cables with black exteriors. Pre-built PCs employ custom power supplies made of lighter, lower-quality materials, particularly aluminium exteriors.
Unlike typical PSUs, which have fans on the top or bottom, these PSUs have fans on the back. They are produced by less recognized companies like Intex and Zebronics and are less expensive than normal PSUs. Standard PSUs have several cables and sleeves but can also have fewer cables or none.
Getting a conventional power supply from a well-known brand is preferable if you want a powerful power supply for your gaming setup.
Size:
The size of the PSU should also be taken into account. Since there are several form factors, not every PSU can be installed in your computer case. So, when selecting a power supply unit, consider the form factor. If replacing your PSU, ensure it fits by measuring the old unit’s dimensions or taking it to the store.
If you’re starting from scratch while designing your system, decide where the PSU should sit, measure its dimensions, and then compare them to the space available within the case to locate the ideal match.
Modularity:
You can attach the cables based on your demands and your system’s specifications using a modular PSU. This feature is absent from conventional, non-modular PSUs, and the wires are fixed to them. Semi-modular PSUs are also available with permanently attached and detachable cables. The main benefit of modular PSUs is that you have more discretion over what to connect and what to leave out.
Doing this can clean up the case’s interior and enhance the airflow and aesthetics, particularly in transparent cases. The proprietary cables supplied by the manufacturer must be used when using a modular PSU; if necessary, aftermarket cables cannot be used.
You must be extremely careful with any new cables you buy for your modular PSU because they might not be compatible even if you use cables from the same manufacturer.
How do I know if the power supply on my computer is bad?
Signs that a computer power supply is failing
- Inexplicable computer crashes.
- Unpredictable blue screen crashes.
- The PC case is making additional noise.
- Consistent PC component failure.
- The case fans are spinning, yet the PC won’t boot.
to Conclude:
Everyone wants their PC to be optimized, whether they use it for work or enjoyment, and your PC’s power supply is crucial to how well it runs. You risk experiencing severe system crashes and malfunctions if your computer doesn’t have enough power to run all of its components.
Therefore, you must ensure that your computer’s power supply is adequate before upgrading it—for example, by installing a cutting-edge graphics card that consumes more power but increases your frames per second. Sadly, How to check the computer power supply is more difficult than other jobs. Instead of using an app, you’ll need to open your PC’s case and examine the power supply in person.
Frequently Asked Questions
How do I know if my power supply or motherboard is bad?
Each PSU cable that connects to a piece of computer hardware should have its connections checked. To find the motherboard light, look inside the case. A defective or improperly connected power supply is typically indicated by flashing lights on a motherboard.
What could cause a power supply to fail?
The most frequent reason for power supply failure is this one. Ingress of moisture, surges and transients, induced power-line surges and transients, lightning strikes, and reactive loads like regenerative motor drives, battery charging, super-caps, etc., are environmental problems.

Stephany Cole, Author and editor at the same time at InstantLobby — Her main focus is to develop strategic editorial and research initiatives for InstantLobby. Her work includes writing, assigning and editing “pillar” collections and other editorial content on technologies and trends of vital importance to CS and IT and business leaders. Topics include Modern technologies such as AI and robotic process automation and IT trends, digital transformation. She spearheaded InstantLobbys Thought series; started from scratch, topics include edge computing, gaming, hyper-automation and high-performance computing, including complex business issues affecting IT and business leaders such as data trust. Previously, she served as executive knowledge and fun.