Fully Modular vs Semi Modular vs Non Modular power supplies – which one should you go for?

A semi-modular corsair power supply unit with cables on a desk with a blurred background.

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If you’re currently confused about what PSU to go for, then we’ve got you covered right here in our fully modular vs semi modular vs non modular PSU guide.

Whether you’re just joining the PC enthusiast community or you’re a seasoned veteran with multiple builds under your belt, you should know that the power supply is one of the most important aspects of your build. With household names like Corsair and EVGA working around the clock to provide you with power-efficient and reliable PSUs (power supply units), this highly competitive segment of the PC component market has given birth to modular units. 

We’ve tested all three types of PSUs and have enough knowledge to let you know the difference between the three and which one you should go for. So, without any further ado, let’s dive in! 

Which PSU type is right for you?

Non-modular PSUs are affordable and come with permanently attached cables, so they are not ideal for those who want to improve the overall aesthetics of their build. On the other hand, semi-modular PSUs have a few cables permanently attached to them, while the rest can be attached/removed whenever required. And finally, fully-modular PSUs have no cables permanently attached to them, something that helps with improving the cable management.

Fully modular, semi-modular, and non-modular PSUs – what are the differences?

If you’ve never built a PC before, then it is important for you to learn about each PSU type so you can get an idea about which one to go for. To help you out, we’re going to discuss the key differences between all three types so you can make an informed decision. Also, we’d recommend checking out what power supplies ratings mean so you know what rating to aim for when selecting a PSU.

Non-Modular PSUs

Black semi-modular power supply unit with cables against a blurred background of computer components.
The Corsair VS450 non-modular PSU with its cables permanently attached – Image taken by PCGuide.

Non-modular power supplies have all of the cables already connected to the power supply. They typically have a less-premium feel than their modular counterparts, have color-coded cables that are not usually braided, and have an overall outdated aspect. Non-modular PSUs are mainly for those who are tight on a budget or don’t really care about the aesthetics of their build.

Still, don’t let that discourage you. Low-end power supplies still function in the same way high-end PSUs do. If you’re buying from a reputable manufacturer and factor in your components’ total power draw before buying, then you should be safe. However, make sure to get at least 80+ bronze certification, as it is an investment in both power efficiency and reliability. 

Non-modular PSUs are also ideal for beginners. Since all the cables are permanently attached, there is no need for you to worry about connecting or managing additional cables when building your PC. However, do keep in mind that this will make cable management difficult, as you’ll have to do something about the unused cables since they can not be removed.

Pros
  • Generally more affordable than modular PSUs
  • Save space as are compact 
  • More reliable as fewer connectors 
Cons
  • Come with a fixed set of cables
  • Limited customization 
  • Not for those who prioritize aesthetics in their PC builds

In case you’re planning to get a non-modular PSU, we recommend checking out the EVGA 550W N1 Series PSU.

EVGA 100-N1-0550-L1 550 N1 550W

Semi-Modular PSUs

A semi-modular power supply unit with peripheral and gpu cable ports, image taken by PCGuide
The Corsair TX550M semi-modular PSU with a few cables permanently attached to it – Image taken by PCGuide.

Semi-modular power supplies only have basic cables attached to the unit, like the 24-pin motherboard connector, the 8-pin CPU cable, and the PCIe power connector that will go into your GPU. Whatever else you may need to power your future system can be connected, so you can customize the power supply based on your needs while having the barebone configuration already installed. For example, cables like SATA, extra PCIe, and other peripheral cables can be attached/removed whenever needed.

In terms of budget, they’re in the middle, with the non-modular on the low end of the spectrum and the fully-modular models at the high end of the spectrum. Value-wise, this might be your sweet spot. You’re getting the best of both worlds while not paying for the full price of a modular power supply. However, do keep in mind that as some cables are still permanently attached to the PSU, semi-modular PSUs can get in the way of improving the overall aesthetics of your build.

Pros
  • More flexibility than non-modular PSUs
  • Can detach unnecessary cables
  • Can help with improving the aesthetics of the build
Cons
  • Cost more than non-modular PSUs
  • Some cables are still permanently attached 

If you’re interested in getting a semi-modular PSU for your build, then you should check out the Corsair CX750M. This is a semi-modular ATX 750-watt power supply and is a great option for cards like RTX 4070 Ti and RX 7900 XT.

CORSAIR CX750M 80 PLUS Bronze Semi-Modular Low-Noise ATX 750 Watt Power Supply

Fully-Modular PSUs

Corsair rm1000x fully modular power supply unit in front of its packaging box. Image by PCGuide
The Corsair RM1000x fully-modular PSU – Image taken by PCGuide.

Modular power supplies allow you to use only the cables you need, making for better cable management, improved airflow, and a much cleaner aesthetic. However, while the modularity aspect is welcomed in almost any build, it also adds a bigger price tag to the component. But if you’re all about aesthetics, then choosing a fully-modular PSU is the way to go.

Unlike non-modular and semi-modular PSUs, fully-modular PSUs have no cables attached to them. This allows you to improve the cable management inside your build, as you won’t have to worry about taking care of unused cables. You can simply use the ones you need and leave the rest of them inside their box.

Fully modular PSUs can help give your PC a cleaner and more streamlined look. Improved cable management also leads to better airflow inside your case. However, compared to the other two types, fully modular PSUs are more expensive, have braided cable sleeves, and are bigger in size.

Pros
  • Best PSU type when it comes to flexibility 
  • All cables can be detached 
  • Provide a cleaner and more streamlined appearance 
Cons
  • More expensive than non-modular and semi-modular PSUs
  • Can be complex for beginners 
  • Detaching cables regularly can lead to wear and tear on the connectors over time

If you’re opting for a fully-modular PSU, then we’d recommend the MSI MPG A1000G. This is a PCIE 5 and ATX 3.0 PSU and is ideal for high-end cards such as the RTX 4090, RTX 4080, and RX 7900 XTX.

MSI MPG A1000G

Which PSU should you go for?

You’re probably wondering “What type of power supply do I need?”, and that’s a pretty fair question. First off, no matter the type of power supply, you need to make sure that it’s power-efficient. You should get at least 80 PLUS certification on your power supply. This means that at 20%, 50%, and 100% loads, it will convert at least 80% of the AC it draws from the outlet to AC, so it will draw 125 watts to output 100 watts of DC. This is important for your power bills and for the safety of your builds and components, as efficiency translates into better temps. As Intel claims, the more efficient your PSU is, the less power it uses, which leads to less heat generation.

Secondly, make sure you calculate the total power draw of your components and pick a power supply with a buffer. So, if your components need around 500 watts, invest in a PSU that’s rated for 650 watts or more. This way, you won’t put your components under stress, you’ll avoid random shutdowns at high loads, and you’ll gain more efficiency, considering that power supplies become more inefficient at higher loads. 

With that in mind, here’s where modularity comes into play. Picking a non-modular power supply is OK if you’re not interested in optimal cable management and clean aesthetics. If your PC case has a PSU cage, then you can use the cage to mask the extra cables without any airflow or visual penalties. 

You should get semi-modular power supplies if you’re interested in getting a value option that also provides you with good cable management design, higher-quality cables, and a better, more premium feel. 

Fully-modular power supplies are very useful in a lot of different cases. First off, they’re most likely better built, with hybrid fans running silently while keeping your unit cooled and premium cables giving you a professional and visually appealing finish. In addition to the premium materials, you can use fully-modular supplies to customize your PC. If you’re building in a small form-factor case, then you can order custom-length cables to maximize the airflow, a crucial aspect to consider when working in small cases. Moreover, you can also order custom sleeves and even individually-sleeved cables to give your build more character. If you want to explore some fully modular options, we recommend checking out the best high-end PSUs.

Conclusion

You should always aim to get a power supply with a higher efficiency rating and with a sensible buffer rather than investing in a semi or fully-modular unit. That being said, the extra money that goes into a fully-modular power supply ensures that you’re getting better-quality materials, better cable management options, and easier troubleshooting in case something goes wrong. If you’re tight on a budget, then you’ll have to skip the extra features and get a non-modular PSU. But if you want better aesthetics and flexibility, then you should definitely opt for either a semi or fully-modular power supply.

Andrew is one of three co-founders of BGFG, the parent company of PC Guide. A keen gamer and PC enthusiast, Andrew dabbles in a bit of writing sometimes - when he gets the chance to!