How To Check What Power Supply I Have: An Ultimate List Of Options

How to check what power supply I have is a question that might usually bother you when you begin playing a heavy game or performing a demanding operation. Whatever the reason, learning about the PSU that you have on your system is important.

How To Check What Power Supply I Have

Thus, this article lists a bunch of authentic ways to discover the hidden specifications of your PSU and states some more valuable stuff. Read on to know your PSU better.

How To Check What Power Supply I Have?

You can check the type of power supply and its specifications by either physically examining the PSU, reaching out to the builder, or visiting the PC manufacturer’s website. Moreover, you can read the user manual or look for the details by entering the PSU model number in the search bar.

– Let the PC Builder Tell You

The way that you choose to follow to check the power supply depends on your PC and your personal choice. If your PC is pre-built, then you’ll need to implement any of the first four ways starting from this option to learn about your PSU. However, if you are a PC builder, then the fifth way will be the easiest for you. 

So let’s start with the easy one. Did you hire a PC builder to build the computer of your choice? Then the same person will be aware of the PSU that is added to your system. Hence, it would be a good idea to reach out to the PC builder and ask about your system PSU. 

Even if the PSU details have slipped away from the builder’s mind, you can expect the same person to open up the case and check the PSU for you. So, the PC builder can save you hours of doubting and trying.

– Don’t Fear Opening Up the Case

Opening the PC case and looking for the PSU inside the same is easy if you are confident enough to pull out the screws. So, once you open the case, you’ll see the PSU located on the back side of the computer. Please look below for the direction details.

The PSU is usually placed at the top. However, you might find it at the bottom in the recent tower computer cases. Moreover, if you consider the all-in-one computers, then you’ll see the PSU on the left or right side.

Do Not Fear Opening Up the Case

Moving further, once you locate the PSU, you’ll need to look for a label on one of its sides. The PSU label will contain the following details about the power supply:

  • Name
  • Model number
  • Voltage
  • PSU Wattage or Power Supply Wattage
  • Maximum current
  • Maximum power
  • Total power
  • Efficiency rating

– Go Straight To the Manufacturer’s Website

If you have a branded PC and the official site of the PC manufacturer has enough information for the customers, then you can visit the same website. Here, all that you’ll need to do is to check your PC model, open your browser, and search for the PC model’s specifications. Consequently, you’ll see the results related to your PC pop up on the screen. Now, you’ll need to select the result that belongs to the respective manufacturer and read the PC specifications.

Although the above idea works well in many cases, you might not get the correct PSU details sometimes. It is because the manufacturers update the features of their products. Hence, it is possible that the model that you are using has been upgraded with a better PSU to fulfill the new users’ requirements.

– Search Through the User Guide

The user guide that comes with the computer contains information about its components. Therefore, you can search through the same to find the details about the PSU. It is an easy way that can be followed by both tech-savvy and non-tech-savvy users. Plus another advantage of using a user manual is that you’ll get accurate details, and you won’t need to doubt if the information belongs to any other PC model.

– Unfold the Receipt

Have you built the PC by yourself? If yes, then you might have the receipt of the components that you bought to build the system. Here, the purpose of mentioning the receipt is that it will have the PSU model stated on it along with the other components. Once you get the PSU model, you can then search for the specifications of the same in your browser.

Consequently, you’ll be able to learn more about the PSU being used in your system.

How Power Supply Cables Affect PC?

As per the above section, different power supplies come with different types of cables. You should study and examine the various cable and connector types to suppress the confusion that is developed while connecting your PSU with the other PC components. Moreover, you’ll be able to build your computer in a short time without causing any damage to your system-to-be. Note that each of your PC’s components requires a particular type of cable.

How Power Supply Cables Affect PC

Here are the cable types that you should be aware of.

– SATA Power Cables

The SATA power cables are used for passing power to the SATA storage devices like the hard drives and SSDs. You can use a single SATA cable to connect multiple SATA drives and avoid creating a web of tangled-up wires. Along with this, mark down that the same cables are supported by some other devices like the fan controllers as well.

– 24-Pin Motherboard Cables

The 24-pin motherboard cables are used for providing power to the components that are directly plugged into the motherboard only. Also, the same cables are used for creating a connection with the motherboard features such as PCIe.

– Four or Eight-Pin CPU Cables

The four or eight-pin cables are used for providing power to the CPU. It is because the 24-pin connectors didn’t prove to be sufficient for transferring the required power to the motherboard features and modern processors.

– Six or Eight-Pin GPU Cables

If you want to create a connection between the power supply and the GPU or the graphics card, then you’ll need six or eight-pin GPU cables. You’ll be amazed to see that the given cables can be configured in different ways to meet the requirements of different GPUs. Please look below to get a list of the possible cable configurations:

  • Six
  • Eight
  • Six + eight
  • Eight + six
  • Eight + eight

– Four-Pin Molex Cables

The four-pin Molex cables fall under the category of legacy hardware. It means that they are outdated, but you can still find them in a few systems. Thus, you might see the same cables on some liquid cooling pumps.

Now, are you wondering which cables have replaced the four-pin Molex cables in most of the systems? Then here is the answer: The SATA cables have replaced the given cables in most modern systems.

How PSU Form Factors Influence Power Supply?

The most notable feature of the PSU is the form factor. It identifies the shape, size, power supply, and other specifications of the component. It must align with the type of the motherboard for getting the PSU successfully installed into the computer. You can have a look at the PSU designs given below to boost your knowledge.

  • ATX

In its earlier days, an ATX power supply came with a single 20-pin main power connector to connect with the motherboard. Contrary to this, now you’ll see it with a 24 -pin power connector. Moreover, remember that the said connector is compatible with the older 20-pin motherboards. Furthermore, the given power supply has an extra rail of 3.3V.

Plus, you’ll be amazed to discover that ATX supports the soft-off feature. The stated feature makes it possible for particular software to switch off the power supply.

  • ATX12V

ATX12V is better than ATX in terms of technical specifications. Thus, you’ll find the size and shape of both of the given power supplies the same. ATX12V is the most common design of the power supply. Its various upgraded versions are available to be installed into the systems.

ATX12V PSU Form Factors

Note that ATX12V 2.1 and ATX12V 2.2 come under the category of the latest versions of the same power supply. The given versions are super efficient and house a 24-pin main power connector.

  • EPS12V

An EPS12V PSU houses an additional eight-pin CPU power connector along with the standard four-pin connector that is also found in the ATX12V devices. If you want to create a highly stable environment for the servers, then EPS12V will prove to be a great option. However, you should not use the given power supply with the home PC components. It is because the same components that are used most commonly conflict with the EPS12V PSU.

  • SFF

SFF represents a small PSU. The SFF power supply is designed to fit into compact cases. You’ll find the given unit smaller than the standard ATX PSU. However, it isn’t less efficient than the other PSUs. Hence, SFF is the best option if you have limited desk space to set up your PC.

Here are some of the SFF power supplies that care about the small cases in your computers:

  • CFX12V
  • LFX12V
  • TFX12V

How To Test Power Supply Units?

You can test the power supplies by either using a paperclip, free software, or a power supply tester. So, move to the below sections to read the detailed explanations of the three techniques:

– Trick Your PSU

This technique uses a paperclip to test the power supply and ensure that the PSU is at least turning on. First, you’ll need to shut down your PC, open its case, and disconnect the PSU by switching it off and plugging out the same from the outlet. Next, you’ll need to carefully detach the cables that connect the various components with the PSU. Also, it would be a good idea to capture a picture of the connected cables or make notes regarding connecting the cables to use the same while reassembling your computer.

So, once you get the PSU detached, you should get your hands on a paperclip. Now, you’ll need to straighten the clip and bend it in a way that the clip looks like the letter “U.” Secondly, you’ll have to look for the 20 or 24-pin motherboard connector. Thirdly, you should see if you can find the green and black pins at the 15 and 16 positions on the said huge connector.

After following the above steps, proceed with inserting the U-shaped paperclip into the green and black pins. The PSU won’t recognize if it’s the pin that powers it on or a random paperclip. Lastly, you should plug it back into the outlet and turn on the PSU switch.

So, can you see or hear the fan moving? If the fan is working, then your PSU is fine enough to be turned on. In the other case, it must be dead because it can’t even turn on in the first place.

– Use a Free Software

Is your PC functional? If yes, then you can test the output of your PSU by using free software such as SpeedFan. The program will read the voltages, temperatures, and fan speeds of all of the PC components. Consequently, it will display the same information on the screen. You can then double-check the readings to ensure that your PSU is providing the required voltage to your system components.

Use a Free Software

If the voltage being passed to the components aligns with the value required by the same, then you don’t need to doubt the efficiency of the PSU. In the other case, you’ll need to find and fix the PSU issue or get the component replaced.

– Get a Power Supply Tester

You can use a power supply tester to monitor the output of a system PSU. So, you’ll need to begin by turning off your computer. Secondly, you’ll need to open the computer case, turn off the PSU, and remove the PSU connection from the outlet. Thirdly, you’ll have to remove the connections between all of the PC components and the PSU.

Once the PSU is left with zero connections with the PC components and the outlet, you’ll have to look for a 20 or 24-pin motherboard cable. Now, look around to see where you’ve kept the PSU tester. Next, connect the tester to the 20 or 24-pin connector and get the PSU plugged into the outlet again. Plus, turn on the unit.

After implementing the steps stated above, you’ll see that the PSU has turned on, and the green light of the tester lights up. Here, if the PSU doesn’t turn on after connecting the same to the tester, then the switch of the tester might be off. Hence, turning on the said switch will make things work.

Now, the tester will perform its work, allowing you to check if the voltages fulfill the components’ power expectations. Please note that +3.3, +5, and +12 can be within +/- five percent in total, and -12 can be within +/- 10 percent. It means that the PSU with voltages outside the given ranges won’t be considered good for your system.

To use the tester to the fullest, you should connect it with each PSU cable one after the other to test all of them. However, don’t forget to switch off and plug out the PSU from the outlet before switching between different cables.

Please consider taking precautions and carefully follow the steps to test the PSU to avoid getting any electric shock or damaging your PC hardware.

Is It Safe To Open the Power Supply Unit?

No, it is not safe to open the PSU because the unit contains capacitors that will give off static electricity when touched. Consequently, it won’t be safe for your system and for yourself to open the PSU and touch its internal components. Even if you choose to unplug the PSU before touching its parts, you’ll still be at risk of getting an electric shock.


How to check what power supply I have is a question with a super-easy answer.

Here are the points that simplify the answer to your query:

  • You can check the fully modular or any type of power supply that you have by reading the label on your PSU.
  • The official website of your PC manufacturer might have the PSU details listed on the same.
  • You can ask about the PSU from the PC builder.
  • The PC user guide contains information about the PSU.
  • You can search for the PSU details online after checking its model from the receipt.

You can always jump to another solution if a particular way doesn’t work for you. Please feel free to come back to read this article again.

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