- PSU Abbreviations and Glossary
- Connectors used in a PC Power Supply
- PSU cables: Non-Modular, Modular and the middle-ground!
- Power Supply Labels
- Power Supply Form-Factor- ATX12V
- Power Supply Form-Factor- SFX12V
- Basic requirements of a power supply
- Facts about 80 Plus Certification
- Protection Circuits and Features
- List of Power Supplies, OEM and Review Links
- Common PC Power Supply Myths
- Resource Links and References
Having a good power supply is important irrespective of the type of system you have- general, gaming and even high-end rig for a specific workload. After all it’s meant to protect your investment and irreplaceable data in your system by providing clean power. But in many cases (usually with general users and gamers in most cases), users have a tendency to ignore this saying that they cannot afford it or they ‘feel’ that they have no need for it. But a power supply protects your system and provides clean power at the same time.
A power supply powers up the components in your computer- from processors to even external storage devices connected to your PC via USB. In a very vague way of explaining power supply converts AC power to DC power that your components use, but in reality it does a lot more than that.
There are many functions within a power supply which protects your components from over-voltage, under-voltage, cooling of components within the power supply and also temperature of power supply. If anything on the power supply goes bad with none of these basic functions, it would most likely damage at least 1 component of your PC. Component manufacturers do not honour warranty on burnt hardware as they believe an end-user may have done something that he/she shouldn’t, including not using a proper power supply.
Peers, users and even many reviewers also tend to give wrong information from time-to-time. Usually, they justify by saying that they never need it. In such cases, users are talking about their older hardware where it didn’t really require to have a power supply with certain specification. In most cases, they advice about gaming and high-end systems when they don’t know a lot themselves. Just like reviews, its best to gather information by asking multiple people and in public so that someone may correct them if its wrong or vague- and this is where forums help.
Those who review power supplies in a wrong manner usually plug it on a PC and run some games, post few pictures of OCCT. These reviews are highly inaccurate and should not be trusted. At the end of the day, components will be the one drawing power from the power supply and not vice versa. You need set of hardware that costs a lot of money to draw power from the power supply under a certain load from all the rails, testing the quality of the power, noise, ripple and also safety features. This all needs to be done with a fixed operational temperature, ideally 40 or better yet 50 degrees Celcius. In a sale-driven country like India where flow of information is erratic and could be misled easily. Even the Tier 1 brands are known to take advantage of this knowing that it would damage their brand name for earning money or getting rid of surplus stocks. Trust me when I say, but those review websites that don’t have equipments to test power supplies are far more respected and hold credibility.
But why do such brands and review sites do this knowing that it’s going to hurt their reputation for promoting reviews with ‘another perspective’? Your guess is as good as mine. But that’s a tale for another day. We can’t make a horse out of a donkey, but as a review source we can help you as much as possible.
Knowing the facts in hand, we do not have the resources to test power supplies. But throughout my time, I have done my best to help people, even have a rough/basic version of power supply written for few local tech forums that have been appreciated for many years before Hardware BBQ was started. At the least we can prepare an updated power supply guide. There are a lot of guides out there are many of the points are valid. But there are some power supply guides with information which was true at the time of writing. Technology evolves, and so do power supply, form factor and other aspects.
One of the hassles such users go through is to identify the component that is potentially damaged. This is a time-consuming process, since you will need to find out the component that is affected, which can only be identified usually either by a physical damage of the components- or by testing them one-by-one on another system till you can narrow it down. You may end up losing your data, and even have other components affected by reducing their lifespan. Therefore, a power supply is one of the important components that you should give some thought before making a random purchase. Buying a good power supply along with the system is the only practice that you should follow. One of the reasons that you should upgrade your power supply is when you install a particular hardware that requires a lot more power.
There have been times where certain manufacturers have given assurances that their product will work even with sub-standard power supplies. They even provide ‘burn warranties’. This is usually a marketing and sales gimmick done out of pressure from their management to gain sales from those users. Exercise caution to protect your investment as they are giving assurance only for their product and not for other components. This is counter-productive, even if by some way what they say is true to the word. Clean power and good protection are vital. Overkill is also counter-productive, which is what we’ll learn from this guide.
Such was a case where a Tier 1 motherboard (and many PC components) brand did in 2009 to compete locally with a similar model and spec from another Tier 1 brand. Certain words such as ‘anti-surge technology’ were thrown around, and written in a way to tempt certain types of users to would risk their investment with a sub-standard power supply. At the same time, there’s an * sign indicating ‘conditions apply’. There was also another Tier 1 brand that wanted to make their memory kit “stand out” in the Indian market, calling it as ‘India-Specific’. Judging by the model number given in the same press release, it was a kit readily available for a bit lower cost, but just to make a quick buck at the cost of brand credibility, they advertised it with the word “India-Specific RAMS”.
This is where ambiguous wordplay works for brands. Usually, I’ve seen it happening a lot in India but they fail to realize that it makes their brand lacks credibility. After reading the entire press release, they don’t guarantee their product will work properly in a clear language, rather they assure that they will repair/replace motherboard at no extra cost. This isn’t limited only to that particular tier 1 brand and not just with just motherboards. Some will use ‘anti-surge’, others will use ‘India Specific’, ‘power saving’ and ‘EMI filtering’. The best and real solution for that is a good enough power supply.
To be fair, certain sub-components may help in fine-tuning the power delivery, but a power supply does all that and a lot more for all of your hardware components. As far as your PC is concerned, a power supply is the source and the source should always be good.
Similarly, there have been power supply manufacturers that have a tendency to go way over their heads trying to justify a good (usually) power supply, by using the words power saving. The “power saving” point will be covered in FAQ, but it doesn’t reflect a brand in a positive light- and it’s counter-productive when a power supply is genuinely good.
Now before we address FAQs, let’s learn about certain basics, starting with the connectors on a typical ATX power supply.
Ampere is a term used to measure electricity. In relation to power supplies, it points out the amount of electric current pushed through the voltage rails on the power supply.
Capacitors are components used to store power, in many electrical and electronic devices. In relation to power supplies, good quality power supplies are able to function provided they are made of good quality. These capacitors are made by several electric component makers, and these capacitors usually have a power and temperature rating.
In relation to PC power supplies, there are two circuits- Primary and Secondary
- Primary circuit takes power from the socket wall (AC power) and through sub-components within the power supply. This includes components that filters and converts AC to DC power.
- Secondary circuit is where the power supply uses the DC power and provides power to PC components via rails.
Lik all components, power supplies need cooling. Like many components- there are two cooling: active and passive. Active uses fans to either push or pull air for the power supply. Passive are usually larger array of sinks to keep the components cool. Unlike active cooling, passive cooled power supplies need a lot more planning to help dissipate properly. Usually, passively cooled power supplies are made for quiet-themed PCs, though manufacturers started using better bearings or fans from better manufacturers and even implemented PWM or thermally controlled solutions.
In relation to PC power supplies, efficiency indicates the usable DC power after converting from AC to DC. During conversion, some amount of power is lost in the form of heat. Having good components and sub-components with higher rating under higher temperature condition usually translates to higher efficiency. Efficiency is rated using % value. Efficiency of a power supply is tested under two types of load using a fixed temperature.
There are two types of load pointed out by manufacturers- Continuous and Peak.
Continuous indicates that the power supply is rated to run maximum amount of power a unit can for a very long time (typically, hours). Peak is a rating that indicates peak power output for a very short amount of time- usually minutes. No good power supply manufacturer will use peak ratings.
Ideally, all power supply manufacturers should advertise Continuous. The ones that advertise peak load should always be avoided at all costs since it provides a certain amount of power for a very brief moment, usually a practically that lower quality power supply uses.
Some manufacturers post both Continuous and Peak. While this isn’t harmful, only continuous power should be given importance to.
Efficiency of load is tested in certain temperature workloads. Since PC is a closed case setup and AC to DC leads to a certain amount of heat, it needs to be tested at a higher temperature condition. Some manufacturers test it at room temperatures to point out high-efficiency value when advertising (some are known not to point out typical temperature). These should be avoided as typically an internal temperature could go up to 40 degrees Celsius depending the ambient temperature. 40 degrees Celsius is the commonly used condition. Some manufacturers are known to use 50 degrees Celsius. In most cases, some claim that this is unrealistic temperature conditions, but manufacturers do this to point out high-quality components, its lifespan/(MTBF) and higher efficiency rating even in seemingly unrealistic temperature conditions. It should also be pointed out that in a closed case PC setup, eventually the system will accumulate dust. Dust is one of the air flow obstacles and when it does block air flow in a power supply, the temperatures would naturally increase. Testing the power supplies in 50 degrees Celcius in my opinion helps to stimulate that condition.
Note that in typical power supplies (even the high efficient variants) have lesser efficiency at lower loads compared to higher loads. This is the reason why proper power supply reviewers test a power supply with variable load- 20%, 60%, 80% and/or 100. The variable load varies from reviewers but typically they point out efficiency in lower power consumption, typical load power consumption efficiency and maximum efficiency it can produce.
Therefore, buying a high-wattage (even the high efficient) power supply for a system that consumes lesser power even at maximum load is counter-productive. One of the typical ways to find the right wattage is by use certain wattage calculate like how Coolermaster has. This helps you to get a rough idea of the wattage unit you should be looking at. Note that CM’s power supply calculator points out wattage, and not amperage. While it does give a ballpark figure, it’s best to check reputed review websites that have proper equipments.
It should also be noted that the quality of the power output degrades in time. Therefore, one of another advantage of using power supplies with better components also ensures long life span of the unit.
In general term, heatsinks helps to remove heat from a particular components by the means of close contact and helps them to dissipate heat by drawing the heat away from the component. It is either dissipated passively or via active methods using air. Commonly, they’re made of aluminum but really good power supplies made specifically for extreme loads use copper.
Abbreviation for Mean Time Between Failures. It’s a unit of measure to indicate the reliability of any hardware component. In relation to power supplies, different manufacturers rate MTBF differently, depending on the series sold for a specific type of uses (general, lower power, gaming, high-end PCs). Like efficiency, Some manufacturers measure MTBF at room temperature, which is wrong considering a close case setup will typically be much higher time a normal room temperature. If an MTBF of a power supply is determined using ‘room temperature’, that means in actual temperature conditions (typically 40 degrees Celsius is considered as ideal operational temperature), the MTBF is significantly lesser as heat will eventually degrade the components on the power supply.
OEM is an abbreviation for Original Equipment Manufacturer. In relation to power supplies, most of the brands get their power supplies made by certain manufacturers. This carries weight when choosing power supplies because depending on the OEM, they do not compromise quality depending on the usage and purpose (general, server, enthusiast grade). Some of the OEMs sell their power supplies in that are available in retail while other OEMs are build-to-order. In many cases, brands are known to re-label the specific OEM units, with minor differences such as casing/ fan colour, brand labels, cable sleeves, etc. Some recommend tweak for additional efficiency, just as increasing the amperage capacity of certain capacitors or adding additional filters and protection circuits.
Not all are OEM though some well-known brands choose well-known OEMs and prefer not to involve themselves in the technical aspects, at least in the start. Some do design their own power supplies, or make certain tweaks on existing OEM models, but they do not have their own manufacturing division for power supplies. The latter is usually the case, whereas some brands prefer the former, but that’s also what sub-standard PSU brands do.
There are two types of PFC- passive and active. Most power supplies that you get now are active, but both should be differentiated for better understanding. In a very basic sense, Power Factor Correction helps to draw AC power from your mains as smooth as possible to ensure smooth operation. This ensures that the power supply draws power from the AC line properly.
Passive PFC is a much cheaper solution but doesn’t really provide a strong PFC protection that a power supply should. In many countries, any power supplies and power bricks with passive PFC function is avoided from being imported. Active PFC is the best implementation for power factor correction and also adds up cost to your existing units. A lot of power supply manufacturers in this day of age prefers to use this for having their product available worldwide.
Stands for Power Supply Unit. The unit is a component that converts AC to DC for computers. It also helps to condition the power meeting certain standards of quality and safety which varies between companies and their series.
In relation to PC power supplies, it means power via different channel produced by the PSU after converting AC to DC power. Modern power supplies need to comply with ATX PSU standards set by Intel. Different channels found in power supplies are +12V, -12v, 5V, 3.3V. It should be noted that some power supplies provide multiple +12v rails. However, its only the ones that have independent channel from the power supply are true multiple +12v rails. Others are usually used as marketing tactic, but in reality they split from the same +12v rail.
In relation to PC power supplies, ripples are usually identified by power supply reviewers with a proper set of equipment with specific functions. Generally, the more ripples a power supply creates while delivering DC power to the PC components, the higher the potential to reduce the lifespan of the capacitors and components. Sub-standard power supplies tend to have much higher ripples which eventually creates instability and even irreversibly damage components.
Major part of the motherboard takes power from the 24-pin Motherboard connector. Some power supplies label them as “20+4” ATX pins. This is because very old motherboards use 20-pins, and if any reason you need to use modern power supplies on much older systems, you can detach the “+4 connector” from the rest of the connectors.
As per ATX power supply specifications, they haven’t been physical changes. But you should know that power supplies that we’ve been getting has the 20th pin with no wire. Don’t be alarmed. This is because this requirement was phased out years ago, since ATX12V v2.01 spec days.
To ensure proper installation, there’s a clip on the PSU side of the connector, which attaches firmly on the motherboards once it’s installed.
4-pin CPU Connector:
It’s a 4 pin connector which powers the area of the motherboard dedicated for processors and its components. It’s also a vital connector that provides power to the processor and must be connected at all times.
8-pin CPU Connector:
It has the same purpose as the ATX12v (4-pin CPU) connector. But it gives either more power or deliver power efficiently via the 8-pin connector.
Almost all power supply manufacturers use 4+4 ATX connector so that it can be compatible with both 4-pin and 8-pin connector on the motherboards. Most good reputed power supplies can split EPs 12v connector into 2 atx12v connector. Other either have one EPS 12v connector or ATX 12v connector. Some motherboards come with 8 pin+ addition 2-4 pin. This usually a feature in motherboards made for extreme overclocking. But this is redundant for those users who aren’t into extreme overclocking and use LN2 as a means to cool down the processor.
Just like the 20+4 pin, these also have detachable “+4” connector and each have clips to secure itself properly the motherboard.
It’s a connector that provides extra power for your discrete graphic card. This is required since the power via the PCIe x16 slots is limited to 75w. By providing extra power, graphic card manufacturers are able to provide higher performance. Some graphics use a 6-pin connector and use some use 8-pin. Some graphic cards require Dual PCIe connectors.
Just like the 4+4 ATX connector, PSU manufacturers have 6+2 PCIe connector so that you can detach the “+2 connector”, depending on the graphic card and the connectors it requires.
This is used by components such as DVD writers, older mechanical HDDs, certain 5.25” fan controller, PC- LED, Cathode tube and other internal add-ons.
These don’t have clips, but the pins on the devices and accessories and the connector on the port is deep enough to keep it in place properly.
SATA power connector:
SATA power connectors are originally made for hard drives, but its naturally used for SSDs as well. These are lot thinner than Molex.
In some motherboards that require more power for multi-GPU based GPU setups, the motherboard has an additional connector to provide power for the PCIe slots. Most motherboards use a 4-pin Molex and some motherboards use a SATA power connector.
Just like Molex, SATA power connector does not have clips, but the connector on the SATA is deep enough to keep it in place properly.
Floppy power connector:
It’s a smaller sized connector which was originally made to power up floppy disk drives, a very old and obsolete storage medium. However, there are certain types of devices which requires floppy connectors- like sound cards. An example is Asus Xonar DX, a discrete sound card that require additional power from the floppy connector.
There are three types- the non-modular, semi-modular and modular power supplies. The reason these are out there is for two reasons- aesthetics and convenience.
Non-modular power supplies:
All the cables in non-modular power supplies are not removable. In the case of having unused cables, you end up usually stuffing them in some area of the case or tie it together with a cable tie and letting it be around. Depending on the case that you have, and the number of wires being used they would add a cable clutter around the case. Some case have that luxury of space where you can hide it, some do not. Most users buy cases with transparent side panel to show off their components, and the last thing such users want is a cable mess. If you take a mini-ITX case, having few unused cables greatly contributes to a clutter within the system, which would be an obstacle for the case’s airflow.
Fully-modular power supplies:
A modular power supply is where you can detach ALL the cables from the power supply unit. This helps you to use the cables that you require. Such power supplies carry an extra premium and usually they’re justified by using it in a very good power supply with high efficiency and reliability.
There are certain aftermarket PSU cable makers that custom-sleeve power supply cables with certain colour combination. Boutique system makers and modders love fully modular power supplies exactly for that reason.
Semi-modular power supplies:
The middle ground is the semi-modular power supply. I’ve heard some call it ‘hybrid’. It doesn’t matter.
This is a healthier option and makes a lot more sense than full-modular. Certain cables that will always be required by the system will be connected- like the 24-pin and 4/8pin ATX/EPS connector. Some power supplies also have PCIe included with the non-removable bunch. The rest are removable- Molex/SATA and additional PCIe.
Unless you REALLY need to have an after-market sleeving for mandatory cables like 24-pin and ATX cables, this is perfect for the masses. Depending on the components used, they cost lesser than fully modular power supplies. This is also a feasible option for manufacturers to implement on a power supply rated for 400- 600w of a certain quality.
Before we get into the types of power supplies made for the PC, we need to note the basic information that ALL manufacturers need to provide on their label.
They are as follows-
This includes the brand name, the name of the power supply and the actual model, country of manufacturer. UL number and safety certifications are also required to be disclosed on the power supply label. This is also one of the places where manufacturers would place the 80 Plus badge. Along with this, there will be a separate label for the serial number of the actual product.
This gives you the information of AC input operating voltage from you socket you can use your PSU with. These differentiate from country to country. The ones that are usually sold worldwide are 100v- 240v. Power supplies that are sold for specific markets are more reserved. Such is the case with power supplies sold specifically for India and China whose input is 220v to 240v.
DC Output Ratings:
I’ve mentioned the different DC output ratings here. For each DC output, manufacturers mention the load in amps it can provide. Ideally, it’s best if manufacturers provide both. Below or above table, manufacturers need to disclose if they have rated the power supply based on continuous or peak.
Along with these labelling, PSU manufacturers are required to put a warning that one should not open up the power supply unless its don by the official service agency for repairs. These are usually posted in few languages, english being the first- along with universal warning signs and/or title.
A lot of manufacturers, including the reputed ones, have a habit of releasing supplies with exaggerated, under-rated and even fake DC outputs. Some, you can only identify when reviewers test it provided its done in proper conditions and with the right testing equipments. Some can be identified by using simple formulas to see if it adds up as actual wattage provided via the voltage rails. Still, testing it with proper equipments is the only way to verify such claims and very few power supply reviewers have such expensive equipment.
One of the most important points for a power supply is the form-factor. Most commonly used form-factors is the ATX design, but there are certain designs made for specific uses and form-factor systems like PICO-ATX.
The types of PC power supplies are as follows:
ATX is the form-factor that most people will use with their PCs. This was originally introduced by Intel along with changes for their motherboard in 1996. At first, the main motherboard power connector was 20-pin, and it came with two voltages- +3.3v and +5VSB. These two voltages enabled the systems to turn on the system without pressing the switch on the PC case (provided its enabled in your BIOS) by pressing the key on the keyboard or mouse. This function is called “Power-on Time”.
Over the years, there have been newer revisions of the ATX specification to meet the requirements of new-age hardware components that users require and desire. Over the revision, power supplies came with extra cabling for graphic cards, 24-pin motherboard connectors, SATA power connectors and so on. As of now, ATX12V 2.x revision is what we’re getting which introduced 24-pin connector and PCIe power connector.
ATX12V form factor has two types of venting design- Top Venting and a non- top venting form-factor.
Top venting is where you have a vent/fan at the base and fan/vent on the AC plug/switch area.
Older power supplies based on top-vent cooling used to have 80-92mm fans on the AC plug and keep a vent on the base. But with additional components and features added to meet higher quality standards, it needed equivalent cooling. The fans were installed on the base, and it enabled the manufacturers to install either 120 or 140mm fan. This is how ATX most power supplies are, but there are non- top vents too. This has become the commonly used design since power supplies are now usually mounted at the base of a PC Case.
In a case of non- top vents, There’s a fan installed towards the AC Plug area and the wire harness area is vented.
For such power supplies, there are certain areas of the casing where the vents are provided. However, the only restriction is such design is that you can only accommodate 80mm fan.
Intel designed SFX (Small form factor) power supply for smaller sized Micro-ATX setups, though in the DIY scene, most Micro-ATX cases that I am familiar with at the time of writing use standard ATX form factor power supply.
Unlike other form factors, this has 5 design variants. The changes and the implementation of the connectors were the same as ATX design, but then there was a newer form factor within the SFX category to provide space for certain components.
Since these variants are present for certain form-factor micro-ATX case design, the mounting hole dimensions are also different. Because of physical restriction, SFX form factors will provide limited power output and hence restrict certain upgradability, depending on the quality of the power supply’s DC output.
The difference between ATX and SFX is only physical. The choice of multiple SFX variants and ATX sized power supply ultimately depends on the case. Usually, such cases come with pre-mounted SFX power supply. Few manufacturers make their own giving a better choice for consumers. Silverstone is the one company that I can find providing SFX power supplies. They also have three SFX power supplies with modular cabling.
A typical SFX power supply has a 60mm fan mounted towards the wire harness area when passive vents at the AC Plug area. The height of the standard SFX is 63.5mm.
Another variant is similar to the standard SFX, but with a slimmer design accommodating a 40mm fan. This allowed the height of the power supply to be a 50mm.
There are two variants in this design. The first one has a longer width of 125mm, but the depth reduced down to 100mm. The second one has a shorter 100mm width, but a 125mm depth.
Now that we’re on the same page about power supply form factors, we can move on and understand the rest. Before we talk about nifty features and everything, first you should know that in a power supply, you will need safety and stability. If these are not covered, no matter how good a power supply is.
Safety is self-explanatory, but safety is an end result of a combination of quality and features put in a power supply together. Good quality components, adequate cooling, proper soldering job on the PCB, quality of the wires and connectors and protection circuits. Remember, a bad power supply can also even catch on fire- and at the very least damage the component, including your hard drives that carry a lot of data.
Output stability is just as important. As said before, there are certain voltage rails, and stability ensures it does not over-deliver that voltage output. Different power supplies react differently during idle/load and the number of devices connected to the power supply.
As per Intel ATX PSU specs, the following are the ideal output voltage specs a power supply that it should be irrespective of the load and the amount of devices used.
Stability is important, especially when the power supply needs to work within the nominal and max value. Power Supplies should shut themselves off if it crosses the maximum output as pointed out by the ATX spec above.
Power Supplies have a certification process, but unlike certifications that are required by certain countries/ continents, this is is more of a voluntary process. A company called Ecova checks the efficiency of a power supply and gives them a certification that identifies a certain efficiency standard.
At first, it started with Bronze, Silver and Gold. Now that 80Plus certification is deemed necessary for ‘easy marketing’, a lot of brands went ahead. At some point, platinum was added, and then came titanium standard which is added to point out excellent efficiency with stellar components tested at seemingly unrealistic conditions. Titanium is the only test certification that tests efficiency at 10% load.
Note that different countries follow certain AC Voltage. For example, United States uses 115 V and India follows 230 v. Most power supplies can be used in countries as it has a variant of 110 v to 230 v. The only time I observed power supply that can be run at a specific AC voltage is for country specific, like Corsair’s China and India specific VS Series that run in countries between 220 v and 240 V.
80Plus tests efficiency with four load settings- 10%, 20%, 50% and 100 with two AC variants.
For 115 v tests, there are a total of 6 certification levels and 230v have 5. There are separate certification for industrial applications (open frame, rack mount, embedded, etc. ) and 230v EU certification.
This is important because there are brands (even the respectable ones) that use their reputation to sneak in a sale. In the case of Corsair VS series, to complete with substandard power supplies a lot of components were used that would not be used usually. If you notice, there is no 80 Plus certification, and it can’t get the ‘standard’ 80Plus certification because that is reserved for 115 V.
Similarly, certain brands are known to use 80Plus certification that their OEMs have achieved for their retail models. 80Plus insists that such brands should get the product evaluated for certification because it is a different brand and may have certain changes. Most OEMs (especially the well-reputed makers) won’t cross a standard of manufacturers, which is pretty okay. Some, however, are not. Reviewers usually find out the OEMs of the power supplies pretty easily, or at better yet- confirm the quality and grade of the components used, including the workmanship like PCB soldering.
The water gets more muddy now. There are some who claim that their power supplies are 80% efficient without the badge. Some power supplies are efficient and companies don’t submit a unit to get an 80 Plus badge as the company charges a fee (probably for both tested and using the certification for marketing purposes). Some don’t do all that. Some use logo designs that are awfully close to 80Plus labelling. If there are no reliable power supply reviews for those units, it’s best to avoid the headache. Otherwise, Ecova has a section that lists the power supplies and the badges their unit have achieved.
It should also be noted that companies make many revisions with existing models. Some point it out along with their power supply names, like “V2“, “V3” or “I“, “II“, “II Pro“. Some are improvements, some are not. Some change their OEMs but don’t mention that to separate themselves from the older models- a classic case of switch-and-bait. It goes without saying that every rev versions should be individually tested.
There is also one more oversight by 80Plus certification. These power supplies are tested and certified at room temperatures. Even if they do hold a certain sign to keep a user away from inefficient and more substandard power supply, this certification shouldn’t be regarded as the best way to choose power supplies blindly. As pointed out previously, in closed case conditions, temperatures rise. Ideally, 40 degrees Celsius is the norm, but 50 degrees is best. One will never know how good the components will hold at such conditions unless it’s tested in this setting.
There are times where manufacturers test and rate them at 40 or 50 degrees Celsius on their own, but It is ALWAYS recommended that one should refer to power supplies reviews that test power supplies properly maintaining operational temperatures of 40 or 50. All information and component overview, including the revision of the power supply (via pictures) is pointed out and disclosed in public.
Power supplies also provide protection circuits. This helps in many situations, usually by cutting off the power to the system and therefore shutting it down before something happens. Some companies that provide AC power cord with the power supply have a small blow fuse on the socket, but that’s not the only fail-safe. The internal safety features are as follows:
Over Voltage Protection (OVP):
As the heading is self-explanatory, this shuts the power off if the output crosses its preset current value.
Under Voltage Protection (UVP):
Like OVP, but shuts off it goes below a particular minimum current.
Over Current Protection (OCP):
If any of the rails pulls more power than it should from the power supply, the OCP switches the power supply off.
Over Temperature Protection (OTP):
If the internals of the power supply crosses a certain temperature threshold set by the manufacturer, it switches itself off.
Short Circuit Protection (SCP):
If anything on the power supply is shorted, it will turn off and even not allow you to start the system.
Surge & Inrush Protection (SIP):
This protection prevents the system from turning on if it detects an influx of inrush current at the time of switching the system on which will ultimately degrade the components.
Brown Out Protection (BOP):
BOP works by protecting the system from low voltages, either by stopping the system from turning on or turning it off.
No Load Protection:
This is a preventive measure in case if there is no load via its output rails. This design is avoided since its interferes with Intel C6 power state feature.
Some of these are deemed essential by known power supply manufacturers, even for the lower wattage/load type power supplies.
There are two issues: usually, the users do not know the value that the power supply manufacturers have set it to. Second- manufacturers don’t really disclose this information. We would not know if a manufacturer have kept these presets in ‘ideal’ values- or if its too close or too far off from ideal values. There is no real standard for this.[divider]
There are certain features that PSU brands and/or manufacturers implement. They are as follows:
Temperature Controlled fans: With the hopes to keep the noise from the system as minimal as possible, some manufacturers have temperature controlled fans which turns on once it reaches a certain temperature.
The better solution in my opinion would be manufacturers having better fans for their power supply or having a PWM controls where minimum load would mean lesser RPM mode.
To make things easier, a list of power supply models, OEMs, rated voltage tables, product link, a review link from power supply reviewers and additional notes are mentioned in the table. I would be trying my best to keep you updated, if one needs anything to be listed, all you can do is mention down in the comment section.
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.
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.
List of trusted power supply reviews:
List of known Power Supply Brands and OEMs:
04.02.2015: Power Supply guide is posted for the good of the wider audience