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The PC Power Supply Guide for the Masses

  1. Introduction
  2. PSU Abbreviations and Glossary
  3. Connectors used in a PC Power Supply
  4. PSU cables: Non-Modular, Modular and the middle-ground!
  5. Power Supply Labels
  6. Power Supply Form-Factor- ATX12V
  7. Power Supply Form-Factor- SFX12V
  8. Basic requirements of a power supply
  9. Facts about 80 Plus Certification
  10. Protection Circuits and Features
  11. List of Power Supplies, OEM and Review Links
  12. Common PC Power Supply Myths
  13. Resource Links and References
  14. View All

Myth #1: More wattage, the better/reliable.

Apart from the usual sub-standard power supply mislabeling, a good power supply manufacturer usually labels their wattage with a bit reserved rating. When that happens, a power supply can technically provide power than the rated wattage.

Additionally, the efficiency kicks in certain at certain load, depending on the make of a power supply. In almost all cases, the efficiency varies depending on the load. Unless you plan on making a large upgrade such a high-end single/multiple graphic card in the near future, its best if you don’t overshoot. Most likely- and hopefully, the variants of efficiency depending on the load may change in the future advancements of power supplies, but as facts are pointed out by most reliable PSU review websites, it’s best to buy based on how much your PC requires.

Some brands use higher quality components for higher wattage rating due to feasibility. Ultimately, one of the components that require a higher wattage graphic cards are power supplies. Now that discrete GPU core manufacturers and its AiB partners are making more efficient graphic cards, usually 400w- 500w is the “bracket” recommendation for single-GPU setups. Some power supplies between 400w-600w have good components, but carry a higher price tag.

Myth #2: More wattage, more power consumption.


As a supplement to the previous myth, the efficiency drops due to low load on higher rated wattage power supplies, assuming the psu you plan to purchase is a good one. As explained earlier, effiency in most currently available good power supplies do not kick in with low load.

Keeping this in mind and assuming its a good power supply: if you have a low-end system that requires 350w-400w, that’s the amount of power that will pull from the power supply.

Myth #3: Modular Power Supplies loses efficiency.

Understand that there are no standard plugs for modular power supplies. That said, earlier when the modular power supplies were a new concept, manufacturers tried different modular plug designs. Some made good contact. Some did not. This was true at some point but at the very least with models made by certain OEMs ensured better contact. Modularity evolved, and the loss of efficiency should be a thing of the past for most widely used brands.

Myth #4: SLI/ CF Certified power supply means I can run multiple GPU irrespective of the wattage.


Though I haven’t seen SLI/Crossfire certified power supplies in a long time, this isn’t true. I am not sure how the certification process works and it’s not really disclosed. That said, the certification seems nothing more than a voluntary system to get a marketing ‘idea’. In my opinion, it didn’t look good because for ‘certifications’, companies end up paying for it. There were many units better than SLI/CF certified power supplies in its class that didn’t need a certification.

Myth #5: Getting two sub-standard/ cheap power supplies is as good as one good enough power supply.


Keeping aside the inability to mount a second power supply in a closed case setup, that’s not how you can efficiency. You will need a power supply that can deliver high efficiency, longer lifespan and safety features which can provide clean power to your hardware.

Myth #6: Power supplies with 5 and 7 years warranty will be better than 3.

Not necessarily

For some brands, in order to keep a good power supply affordable they skip certain features and even getting a 80 Plus certification. They also reduce the warranty periodto keep the servicing cost down, or so I’ve been told.

Similarly, not many brands are very upfront about their warranty process. Some provide direct replacement for a certain period within the warranty timeframe. Some provide refurbished or repaired unit for the rest- or give a power supply from the lower series. Some do give the same version but that probably would mean the manufacturing newer makes of the same model could be lesser for several reasons. As said before, power supplies ultimately will degrade and quality of the components determines the lifespan. Warranty is a safeguard to protect users to get a newer unit in anything goes bad, not a guaruntee that the power supply will be in the same stellar condition till the end of the warranty period. If you choose power supplies with higher grade components, you have nothing to worry about.

Myth #7: Only certain OEMs can make good power supplies.

Not really, though it does seem to look at a fact at times even from my perspective.

As said before, some brands directly re-label OEM’s existing models and stays away from the technical aspect to concentrate on marketing side of things, some design their own and some implements few tweaks here and there based on the existing units.

At the same time, some OEMs have retail versions, whereas some are made-to-order. Handful of OEMs do have a reputation of not degrading after a certain point to maintain their reputation. Some OEMs will make anything what their clients ask, provided it means a minimum set of standards.

It’s the opposite for substandard PSU makers and re-labelers. Way too much time has past and its not easy to teach old dogs some new tricks. They will always see it from a profitable perspective, even if it irreparably damages their reputation.

Tracking OEMs has its benefits of knowing their past power supply makes because there are certain aspects we can judge on- especially workmanship and soldering quality. Many OEMs like Seasonic who also have retail power supplies have that reputation, but so do other OEMs like FSP, Seventeam, Enhance, etc.

Myth #8: Only a handful of power supply brands are good!

That’s true and false on a case-to-case basis.

Some used to have a good reputation of making great power supplies in the past, but now are cashing in on their past reputation and have a set of questionable power supplies. Some pratically destroyed their reputation in the past with massive marketing and channel efforts, but now have learnt and try to turn a new leaf. For some, old habits die hard. Some try to stay the safe side by choosing a generically known good OEMs by relabelling existing retails versions.

Three different situations which applies for any manufacturers. Some readers know which brands are indirectly referred here, but this can be applied in any situations irrespective of the brand name. Don’t judge any components by the brand, rather judge by the product in hand.

Myth #9: Heavier the better

It’s best if one doesn’t follow that, even if the general concept is true up to a certain limit.

While weight is one of the factors that differentiate good from sub-standard power supplies, but that’s because due to the lack of components on sub-standard power supplies. Besides, substandard PSU makers can easily take advantage of that opinion by having “heavier power supplies”. It should also not be a factor to judge a series of good power supplies.

Myth #10: Low-cost/wattage system can use sub-standard power supplies

If you still have that mindset, that means you haven’t read this guide.

There was a time when the currently labelled sub-standard power supplies did the job, but that was a very long time ago. Technology evolved, and required to have cleaner power source. Every ATX specification disclosed have a tolerance value per rail. But if you want to risk it by saving a small amount of money over a larger amount of investment, no valid points will educate you unless experience teaches you the hard way.


  1. Koolest ripper guide to What is and what is not on SMPS!
    Thanks for adding those SMPS suggestions! 🙂

  2. Much appreciated!

    I plan on putting more guides per component so that many people from newbies to regular users can understand “what is” and “what is not” for many components to help them make better purchase decisions! This way, we can guide even the newest of end users to understand whenever they read our reviews!

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