Update: 1/23/13: Due to overwhelmingly positive feedback and a number of reader questions about the actual origin of certain power supply brands, we thoroughly revised our Who’s Who of PSUs, originally published in November of 2010 and last refreshed in May of 2011. Since the article is frequently quoted and linked to, we’re updating it rather than publishing the newest entries. As such, much of the content remains unchanged from the previous version.
Today’s revision adds many new manufacturers and brands, though. It also expands the number of models in several product families. Indeed, much has changed since our original article appeared more than two years ago, and we’re happy that readers in our forums and around the Web appear to be better informed and more discriminating when it comes to picking out a new power supply.
At the same time, manufacturers also appear to have re-evaluated some of their practices, and we’ve seen newer models use better components, resulting in higher quality overall.
We want to extend a special thanks to our community, as many of our readers and forum members have contributed much helpful information and valuable data to this analysis.
Several companies also joined in for the first time, volunteering information on their product lines. Sadly, for now it still appears that this is the exception rather than the rule. Many of our emails asking for information were met with silence. On that note, we acknowledge that we’re not infallible. Should you come across any omissions or errors, big or small, we invite you to send us your feedback so we can keep expanding and refining this list, ensuring it remains current and as inclusive as possible.

This article first appeared on November 12, 2010, and has since been added to and updated.
Who’s Who?
Let’s start by dividing the manufacturers into three large groups so we can better understand the database and how these companies are connected:
1. The OEMs (Original Equipment Manufacturers)
OEMs manage all of their production internally. They either exclusively design and manufacture their own PSUs (like Enermax) or design and manufacture their own brands, as well as manufacture PSUs designed by other companies (such as FSP, HEC, and SeaSonic). Some of them focus heavily on worldwide exports and provide a range of models, which are then sold under different labels. It's common to find otherwise-identical models marketed under many different names and labels. The industrial areas around Shenzhen, China, are the cradle of the lowest-priced PSUs sold all over the globe.
2. Designers: Without Their Own Production
The second group of companies also develops and designs their own products. However, they have to outsource either some or all of the manufacturing to other companies. One example of this is Be Quiet. Those familiar with the brand noted how Be Quiet P7 models were suddenly much better than the disappointing P6. The answer was simply a manufacturer change, from Topower to FSP. Other examples of designers include SilverStone, Corsair, PC Power & Cooling, and Tagan.
3. The Labels: With or Without Any Technical Involvement
Arguably, this group could be subdivided. Some importers of foreign PSUs that resell models under their own labels have a certain influence over the quality and choice of components, while others simply bring in some very cheap products, change the label, and resell them.
This third group is the most interesting one for price-oriented customers, though also the most uncertain for quality. You're as likely to score a bargain by getting a relabeled high-quality product at a lower price as you are to be disappointed by being too tight-fisted. Some good examples of products to watch are new models from Aerocool, which are essentially the Cougar units from Compucase/HEC with a discounted price and completely restyled exterior.
After many tests and inspections of budget models (by us, our readers, and friendly computer stores), we would advise you to steer your piggy banks clear of the labels Rasurbo, Inter-Tech (Sinan Power, Coba), Tech Solo, LC Power, RaptoxX, Tronje, Xilence, Ultron, World Link, Q-Tec, etc. We were able to identify some of these models without looking at the UL number simply by checking out the installed components. These were almost exclusively the simplest work of such manufacturers as Enhance, World Link, Andyson, Topower, Casing Macron, and Channel Well.
Lack of protection circuits, low efficiency, and bad build quality were major points of criticism. The lowest of the low was a European label called Hardwaremania24, targeted at OEM PCs. While still in standby mode, the PSU heated to about 176 degrees Fahrenheit, spent the next six hours billowing smoke, and finally made what might be described as a trumpeting sound before dying. The host computer was never even turned on. After analyzing the PSU, we found no protection at all save for a single slow fuse.
How do you identify a bad power supply before buying it?
- Extremely high wattage claims at comparatively low prices are suspicious. There are simply no decent 750 W power supplies for $50. For every product class based on performance and features, there must be a minimum price. When a product is significantly below that price, be cautious. You can get a "400 W PSU" for $20, and such fire hazards are installed in budget PCs every day by unscrupulous companies that know exactly the risk they're handing off to buyers.
- Check the specifications. For example, if a PSU claims high performance on the 3.3 and 5 V rails while the 12 V rail numbers are low, then you know something is wrong.
- The manufacturer does not specify any combined maximum performance, but instead only shows the maximum load for each rail separately. This is done without specifying how much real power would be available if all rails are used at the same time. Avoid PSUs without this information.
- Be careful with juicy marketing expressions and commercial lingo: Super, Extreme, Gaming, Combat, etc. Using superlatives to describe something quite normal should arouse suspicion and have you double-check specification details.
- Passive rather than active Power Factor Correction (PFC) leads to lower power efficiency.
- Very few or short power connectors and cables might be an issue. A 750 W PSU usually has four PCIe connectors for graphics cards (2 x 6-pin and 2 x 6+2-pin), so think twice if a model only offers two (or at least consider your upgrade options).
- With cheap PSUs, the quality of the cable insulation may be poor, or the cables may not be insulated at all. The power cable grommet may also be insufficiently padded.
- Be careful if there are few or no indications of protection circuitry. If the PSU specification only says OPP (overload protection) or perhaps SCP (short circuit protection), this points towards a normal fuse. If the specification also says OVP (overvoltage protection), this probably means that it is equipped with a simple metal oxide variable resistor. These security measures by themselves are absolutely insufficient and cannot replace any kind of digital safety chip.
Unfortunately, you can't always tell at first glance whether you're dealing with a high-quality PSU or whether there's nothing but disappointment waiting behind the pleasant facade. Therefore, we decided to open up two budget PSUs representative of what you can find in many of today’s OEM PCs and illustrate the points and features you should be examining.
A First Look At the Inside: Primary Capacitor and PFC
First, look at the storage capacitors in the primary circuit. These act as buffers and help protect the PSU and computer from voltage fluctuations. The electrolyte used in them is key, because it evaporates or dries out through a combination of heat and time. As a general rule, capacitor lifetime is halved for each 10 degrees Centigrade increase in temperature over the specified normal load. Using higher-quality capacitors that can handle 105 degrees instead of 85 degrees (C) should almost double their lifetime, greatly contributing to the PSU's durability.
A PSU equipped with a big choke like in the photo above is a clear indicator of passive Power Factor Correction (PFC). Only more sophisticated active circuitry allows for factors close to the optimum value of 1, while passive components can reach 0.7 to 0.8 at best. The type of power factor correction indirectly suggests the expected efficiency of the power supply. Although PFC and efficiency are casually unrelated, devices with active PFC are also usually more complex and modern, meaning you're more likely to get better efficiency from them.
Protection Circuits
Even without opening the PSU, a data sheet can reveal some of the safety measures taken (or not) by manufacturers. A decent PSU should contain the following safety measures:
- OCP (Over Current Protection): protection against power spikes
- OVP (Over Voltage Protection)
- OPP (Over Power Protection): overload protection, sometimes called OLP
- OTP (Over Temperature Protection): protection from overheating
- UVP (Under Voltage Protection)
- SCP (Short Circuit Protection)
- NLO (No Load Operation): this isn’t exactly protection in the same sense as the other features, but it allows the PSU to power up and function normally, even with no load.
Without this information, you have to look inside the PSU to find out what you need to know.

We found no protection at all on this unit, except for a simple fuse. Sadly, this PSU is still available on the market under a couple of different labels.
Passive components do not guarantee sufficient protection. Without a digital security chip, the computer hardware is severely exposed to risks.
The security chip PS223 from Silicon Touch is popular, and you should avoid PSUs not using it or similar products, such as the PS332S.
Cables and Short Circuits
You can tell a lot about your PSU by looking at its internal wiring. A lack of heat shrink tubing, carelessly exposed solder joints, and components fastened with a glue gun are symptomatic of cheap and hazardous manufacturing. If unprotected cables are placed next to hot components, a PSU failure is nearly assured.
Boards
A final quality indicator is the circuit board material. Impregnated laminated paper (like the yellow boards in the pictures) is a sure sign of cost cutting. Fibre materials are much more durable and, perhaps more importantly, non-flammable.
UL Numbers From Underwriters Laboratories
"Underwriters Laboratories, an independent firm working with product safety certification, has been active in the field of product testing and preparation of safety standards for more than a century. UL evaluates more than 19 000 types of products, components, materials and systems annually. Every year more than 20 billion UL marks are placed on products from 66 000 different manufacturers. The UL Group and its network of service providers include 68 testing and certification labs worldwide, serving customers in 102 countries."--From the About UL page at ul.com
Essentially, this means that all PSUs sold on the North American market must be marked with a UL number. This number should identify the actual manufacturer of a product. However, not every PSU has such a number. UL number omission on a North American product might indicate poor quality.
Step 1: Reading the UL Number
To find the UL number, there's no need to open your PSU or de-solder anything. Simply open your PC and look at the power supply's label. The UL number usually begins with an "E" followed by a string of numbers. See the three examples below.

If your PSU has such a number, you can move onto the next step, finding out what it means.
Online UL Number Query

Now let's find out more about your PSU. Go to the UL Online Certifications Directory and enter the UL number in the UL File Number field. If the number exists in the database, you should immediately see the result. If not, the number is invalid, fake, or the manufacturer no longer exists.


Companies: 2The Max Asia Pacific, 3Y Power Technology, Ablecom, ABS, AcBel, A.C.Ryan, Achme, A-Data, AeroCool, Ahanix, AHCOF, Aikou, Akasa, Amacrox, AMS, Aopen, Andyson, Antec, Aopen, Apevia/Aspire, Apex, Arctic Cooling, Artesyn/Astec, Astec Int. Ltd., Asus, Athenatech, ATNG, Atrix, Avance, Axle, AXP, Azza, Be Quiet!, Bestec, BFG, Bgears, Boser Technology Inc., Broadway.


Companies: C-Young, Casecom, Casing Macron, Channel Well, Chenbro, Chieftec, Chill Innovation, Club 3D, CompUSA, Coba, Codegen, Comix, Conda, Cooler Master, Cooling Well, Coolmax, Cooltek, Corsair, Cresun, DAR, Dbetter, Deer, Dell, Delta, Dongguan Zhangmotou, Dynapower, Dynex.


Companies: E-Star International, Eagle Tech, Elwin Technology Ltd., Elec, Emerson Network Power, Enermax, Enhance, Enlight, ePower, Etasis, Etopmay, Flextronics, Fob, Focus, Forepoint, Fortrex, Fortron, Foxconn, Foxlink, Fractal Design, Frisby, Fujitsu Siemens, Glacial Power, Gigabyte, Global Bright Intl., Globalwin, Gold Pal, GrowUp Japan, GPS, Great Wall, GTR, Guizhu, Hama, Hardwaremania24, HC, HEC, Highscreen, High Performance Group, High Performance PC, High Power, Himere, Hiper, Hipro, HP, Huntkey.


Companies: ICP, Ikonik, Impervio, Inter-Tech, In Win, IOK, I-Star, Jada, Jeantech, Jet, Jehovah, Jersey, Jiumeng, Jiu-Peng, JOU JYE, JPAC, Just PC, Kaibo, Kaisen, Keega, Key Mouse, KinEagle, Kingwin, Koolance, L & C, LC-Power, Leadman, Leadway, Levicom, Li Shin, Lian-Li, Lite-On, Linkworld, Logisys, Mad Dog, Mapower, Masscool, MaxInPower, Maxtro, Mean Well, MGE/XG, Micor, Minlong, Mitac, MSI, Mushkin, Mutantmods.


Companies: NesteQ, Newton, Nexus, Nipron, nMediaPC, North P, NorthQ, NOX Extreme, NZXT, OCZ, Okia, Pangu, PC Power & Cooling, Point of View, Powercase, PowerCooler, Powerex, Powerleap, Powerman, Powertek, Powmax, Procase, Q-Technologie, R-Senda/Rsenda, Raidmax, RaptoxX, Rasurbo, Recom, Revoltec, Rhombutech, Rocketfisch, Rosewill, RSD.


Companies: San Hawk, Sansun, Sanyang, Scythe, Seasonic, Seventeam, Sharkoon, Shinlion, Shuttle, Sigma, Shanda, SilenX, Silverpower, Silverstone, Sinan Power, Sino Tech, SinTek, Shanda, Sirfa, Sirtec, Skydigital, SMD, Solytech, Sohoo, Soyo, Sparkle Computer, Sparkle / Sparkle Power, Spec Research, Spire, Startech, Sunbeam, Sun Pro, Sunfone, Sunyo, Super Flower /SFC, Supertalent, Sytrin, Tagan, Taiwan Youngyear, Task, Techsolo, Thermaltake, Thortech, TMC, Tommade, Topmay, Topower, Top-Power, Towin, TS-Power, TTGI, Tuniq, Tyan.


Companies: Ultra, Unitek, Vantec, Win-Tact, Wintech, Wiseframe, XClio, Xigmatek, Xilence, Xion, X-Spice, Yesico, Zalman, Zippy.
We want to stress two things in particular:
A PSU is not necessarily bad because it is cheap. But the lower the price, the more you'll likely have to skimp on safety and performance features. A high-quality PSU contains more expensive components. If you buy cheap, you might have to buy twice--or more.
A PSU is not automatically inferior because it was made by a contractor with which you aren't familiar. These companies make all kinds of products, from luxury brands to pure garbage. Again, it's a question of hitting different production targets. Is the product built for quality or aggressive cost reduction? The responsibility always lies with the buyer to recognize and reject products that are obviously unsuitable.
In the light of the previously presented tables of manufacturers, some quality issues, such as those seen with Be Quiet's P6 series, present an additional aspect to consider. We can also see that companies like Super Flower are often underestimated because they are not seen and accepted as the large manufacturer, which in fact they are.
We thank our readers again for their help. We will continue to collect new results and regularly update the lists. They are, after all, a rough guide to what goes on behind the scenes in the power supply industry.













