Power Conditioner Buying Guide

Power Line Conditioning for Computers, Electronics & Audio/Video Equipment

This buying guide will help you:

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• Understand what a power conditioner is and recognize key features
• Learn the questions to ask when purchasing a power conditioner
• Find answers to frequently asked questions about power conditioners

Power Conditioner Basics

What is a Power Line Conditioner?

Also known as a voltage regulator, a power conditioner protects sensitive electronics, such as computers, lab equipment, home theaters from voltage fluctuations and power surges. It also removes electromagnetic and radio interference from the AC line so amplifiers, radios and other audio/video equipment perform at their best.

Why do I need a Power Conditioner?

Nominal voltage is the name given to a range of voltages. In North America, nominal voltage is 120V, but for a variety of reasons, you will rarely get exactly 120V from the outlets in your home or office. Power companies try to maintain actual voltage within ±5% of the nominal voltage (114–126V in North America, 228-252V elsewhere) but more significant over- and under-voltages can occur.

When the power supply to a device falls out of the service voltage range, the device may shut down, malfunction, or suffer damage to its circuit board. Poor power quality over an extended period may cause premature failure of the device. Power conditioners with Automatic Voltage Regulation will trim or boost voltage to maintain the service voltage range.

What causes voltage fluctuation?

These are some of the more common causes of voltage fluctuation.

Changes in demand for electricity in the power company's system due to factors such as weather or time of day

The distance of an outlet from the meter or from the meter to the power company's transformer (power pole)

Proximity to a factory or other large consumer of electricity

Starting or stopping common household appliances, such as a refrigerator or vacuum cleaner, especially on an already overloaded circuit

What benefits can I expect from a Power Conditioner?

• Protect sensitive electronic equipment from damage or data loss
• Improve the quality of audio recording or playback by removing line noise that causes "hum"
• Extend the life of equipment containing electronic circuits

Key Features

Automatic Voltage Regulation (AVR) – Stabilizes incoming AC power by boosting low voltages and trimming high voltages so connected devices get the voltage they were designed to use (nominal 120V or 220-240V, depending on your country). Voltage regulation is sometimes called "buck and boost".

"Let-Through" Rating – The let-through voltage rating refers to the average amount of voltage the power conditioner "lets through" to connected equipment following a surge or spike. The lower the let-through rating, the better the surge protection. The UL rating levels are 330, 400, 500 and 600 volts.

Joule Rating – A power conditioner's joule rating indicates how large a power surge it can absorb without failing. You should choose a joule rating based on the value, importance and sensitivity of the equipment that will be connected to the power conditioner. For more sensitive or costly equipment, such as computers, televisions, lab equipment and audio/video equipment, select a power conditioner with a rating of at least 1,000 joules.

Line Noise Filtering – Line noise is the result of electromagnetic interference (EMI) and/or radio frequency interference (RFI) and is typically caused by other equipment operating on the same electrical circuit (e.g. fluorescent lights or a vacuum cleaner). You may experience line noise as a buzz or hum from your speakers or radio transceiver, or "snow" on a television picture. Line noise filtering removes noise from the incoming AC power and is expressed in decibels (dB), with a higher dB rating indicating better noise suppression.

How to Choose a Power Conditioner

These five questions will help narrow down your choices.

1 How much power does your equipment need?

To estimate power capacity requirements, add up the wattage of the devices you plan to connect to the power conditioner. Refer to the nameplate or manufacturer's documentation for each device to find its wattage. If output is listed in amps, multiply by the nominal AC voltage to estimate wattage (e.g. 3 Amps x 120 Volts = 360 Watts).

2 What voltage does your equipment use?

The AC input voltage of the power conditioner should match the voltage of the equipment connected to it. For homes and offices in North America, the voltage is typically 120V and the input plug type is NEMA 5-15P, which is the familiar grounded power plug used in most households. In Europe and elsewhere, nominal voltage is typically 230V and the plug type will vary from country to country.

3 What type and number of outlets do you need?

Count the number of devices that you plan to plug into the power conditioner and choose one with at least that many outlets. Also pay attention to the input and output plug types. The power conditioner's input plug and outlets should match the plugs on the equipment you'll be connecting.

Plug Type: NEMA 5-15P
Voltage: 120V
Rated: 15A Plug Type: NEMA 5-20P
Voltage: 120V
Rated: 20A Plug Type: NEMA 6-15P
Voltage: 230V
Rated: 15A Plug Type: IEC-320-C19
Voltage: 230V
Rated: 20A

4 Which form factor works best?

Tower - A tower power conditioner is shorter in width than height (or roughly the same) and typically has outlets in back. It can be placed on the floor behind the equipment it is protecting, or on a desk or shelf.

Rack Mount - A rack-mount power conditioner is specially designed to be mounted inside a standard 19-inch rack enclosure or open frame rack (almost all racks use the 19-inch standard). The power conditioner's rack height tells you how many vertical rack spaces it will require. One rack unit (abbreviated to 1U) is 1.75 inches (44.45 mm) high. Outlets are typically on the back of a rack-mounted power conditioner.

Wall Mount - Some power conditioners come with mounting "ears" so they can be securely attached to a wall or bench, saving floor-space and preventing accidental disconnections.

5 How valuable is the equipment attached to the power conditioner?

The value of the equipment you want to protect is the most important consideration when choosing a power conditioner. Devices that are critical to work/home life and those that are otherwise costly or fragile require a greater degree of protection.

A power conditioner's job is to regulate voltage and to absorb the brunt of power surges and spikes so your equipment doesn't have to. This will take a toll over time. In addition to AVR and good Joule rating, look for models that come with insurance to repair or replace any connected equipment damaged by power surges (USA, Canada and Puerto Rico only).

Other Features to Consider

C14 Outlets - C14 to C13 power cables are a popular way of connecting a server or switch to a power source in a server room or network closet. A power conditioner with a mix of NEMA 5-15R and C14 receptacles provides options for connecting and placement of devices.

LEDs for Power Monitoring - Real-time diagnostic LEDs indicate if your incoming voltage is being boosted or trimmed. They can also detect common wiring faults in wall outlets, such as loose wiring or improper grounding.

Electric Powertek contains other products and information you need, so please check it out.

Input Breaker - A resettable breaker protects the electrical circuit from excessive current draw. If the breaker trips, you can remove some of the equipment plugged into the power conditioner and reset the breaker.

Physical Size - Most tower line conditioners are small, but extra-small models are available for especially tight spaces, such as a shelf or behind a piece of equipment.

Power Conditioner Comparison Chart

Form Factor Tower Small Tower Wall-Mount Rack-Mount Input Voltage 120V or 230V 120V or 230V 120V 120V Output Wattage Up to 2,400W 600W 600W 2,400W AVR Range 85-147V
189-247V 89-147V
189-247V 87–140V 89-147V Surge Suppression - joules 340-720 joules 720 joules joules Noise Filtering Up to 80 dB 20 dB 20 dB 80 dB Outlets Up to 6 Up to 6 4 14 Explore Explore Explore Explore

Alternative Power Quality Solutions

Isolation Transformers

An isolation transformer transfers electricity from a primary circuit such as the AC power supplied by an outlet, to a secondary circuit such as a medical device or lab instrument, without a physical connection between the circuits. The electrical isolation protects against electric shock and suppresses electrical noise that can interfere with sound quality.

Explore

Surge Protectors

The main job of a surge protector is to protect connected equipment from power surges above the surge protector's "let through" voltage. Some surge protectors also filter out line noise from incoming AC power supply.

Explore

UPS Systems

A UPS with AVR does everything a surge protector or line conditioner can do, plus it includes a battery that allows equipment to remain powered through short-duration power failures. Like power conditioners, many UPS systems have voltage regulators that keep voltage in an acceptable range.

Explore

Product Features Compared

Surge Protectors UPS Systems with AVR Power Conditioners Isolation Transformers Protection Against Surges and Spikes Protection Against Brownouts EMI/RFI Line Noise Filtering Voltage Regulation † Battery Backup Power Electrical Isolation Typical Street Prices (USD) ‡ $40 $150 $200 $350 Explore Explore Explore Explore

Questions & Answers

What is an acceptable voltage range for a 120V circuit?
In the United States, National Electric Code article 210-19 FPN No. 4. suggests a 5% maximum combined voltage drop on the feeder and branch circuits to the furthest outlet "will provide reasonable efficiency of operation." The Canadian electrical code also requires no more than a 5% drop between the meter and outlet. Applying the 5% tolerance gives a nominal 120V range of 114V to 126V.

Can I use a power conditioner with my generator?
Yes, a power conditioner will stabilize the voltage from a generator. However, it will not convert the modified sine wave produced by some generators to pure sine wave, making those generators unsuitable for sensitive electronics.

How to Choose the Best Power Conditioner for a Guitar Amp
See https://blog.tripplite.com/https/blog.tripplite.com/how-to-choose-the-best-power-conditioner-for-guitar-amp

Should I use a power conditioner with my laser printer or copier?
Yes, but not with the printer itself. Printers and copiers use a hot roller called a fuser unit to bind ink toner to the paper as it passes through the printer. Periodically, the printer needs to reheat the fuser unit to the required temperature, and this requires a lot of electricity. To prevent a power sag (under-voltage) from impacting computers and other sensitive equipment on the same circuit as the printer, use a power conditioner with Automatic Voltage Regulation (AVR).

Connecting a printer to a line conditioner may prevent the printer from getting the voltage it needs. A better approach would be to have a qualified electrician check the capacity of the existing line and add a separate circuit for the printer if necessary.

What is the difference between voltage fluctuations and a power spike or surge?
A power or voltage spike is a sudden increase in voltage, ranging from a few hundred volts to tens of thousands and lasting between 1 and 30 microseconds. A power surge is like a spike but lasts longer. Voltage fluctuations are normal and do not typically harm equipment connected to an outlet. Over- or under-voltages occur when the voltage reaching powered devices falls out of the normal service range.

Why does my power conditioner make a clicking sound?
As a power conditioner corrects high or low input voltage, it will make a gentle clicking sound. The frequency of the clicking will depend on the quality of the utility power in your area. The clicking is normal, and no action is required on your part.

Does a power conditioner improve sound?
A power conditioner can potentially improve sound quality by providing a cleaner and more stable power supply to audio equipment. Power fluctuations and electrical noise can interfere with the performance of audio equipment, leading to degradation in sound quality. By conditioning the power, a power conditioner can reduce the amount of electrical noise and provide a stable voltage, which can result in improved sound quality.

However, it is important to note that the effect of a power conditioner on sound quality can vary depending on the equipment and the specific electrical problems being addressed. In some cases, the improvement in sound quality may be minimal or not noticeable, while in other cases it can be significant.

Is a power conditioner a surge protector?
Not all power conditioners are surge protectors, but some include surge protection as part of their functionality.

A power conditioner is an electrical device that improves the quality of the power supplied to an electrical load by regulating voltage, reducing noise, and filtering out electrical disturbances. The goal of a power conditioner is to protect sensitive electronic equipment from damage caused by power fluctuations and electrical noise.

A surge protector, on the other hand, is specifically designed to protect electronic equipment from damage caused by power surges and spikes. It accomplishes this by diverting excess voltage away from connected equipment.

Some power conditioners include surge protection as part of their functionality, effectively combining the two functions into a single device. In these cases, the power conditioner can improve the quality of the power supply while also providing protection against power surges and spikes.

Should I use a power conditioner or isolation transformer with my guitar amp?
If improved sound quality is your primary goal, an isolation transformer is the best choice. Microphones, instruments and amplifiers can pick up unwanted hums or buzzes if they are plugged into the same circuit as items such as fluorescent lights, air conditioners and dimmer switches. If your band is playing in a bar, even the bartender's blender is a potential source of interference!

An isolation transformer uses two coils of copper wire, wound so that the primary coil connected to incoming AC power induces a current in the secondary coil powering connected devices. Since there is no direct connection between the coils, musical instruments and recording equipment attached to the secondary coil are isolated from audio frequency noise on the power line.

Why Buy from Eaton?

We know you have many brands to choose from. On the surface, they may all seem alike. It's what you don't see that makes the difference. With Eaton, you get solid engineering, proven reliability and exceptional customer service. All our products undergo rigorous quality control before they are offered for sale, and independent testing agencies verify our products meet or exceed the latest safety and performance standards. Our commitment to quality allows us to back our products with industry-leading warranties and responsive customer service. It's the Eaton difference.

Are you interested in learning more about Power Line Hardware? Contact us today to secure an expert consultation!

Quick Preface: I am willing to update this post as needed with more information (or corrections) if approved or agree to have it taken down if a TPU staff or writer wants to take charge and do a more thorough (and TPU-stamped) write-up. I get asked for advice on this now and then and now that there's a dedicated forum section, I thought I'd put together some recommendations. This guide is intended as a general set of recommendations based on current information and currently released (at time of writing) products. TPU published a guide in based on PSUs they reviewed and it still has a lot of great information.

SO, you need a power supply. Here are some general recommendations for choosing a supply that's right for you.

TLDR: 1. Figure out how much power you need. 2. Figure out what budget you have and don't skimp on the PSU. 3. Factor in all your other needs (cable lengths, noise, etc.) and read reviews before final selection.

1. How much power do you need? There are several different opinions on the best way to figure this out, but ultimately this is where to start.

• You can use a variety of web power calculators to give you a ballpark of your needs:
  • PCPartPicker - put your parts in and then it will give you an estimated wattage. This one is very basic, but it does provide a breakdown of the larger-power-draw parts.
  • Extreme OuterVision Power Supply Calculator. This one has lots of variables and options that help you really dial in your use-case.
  • Newegg has a simple one, as do many power supply manufacturers (example 1, example 2). You can try putting your parts into several and then do an average (or pick the most conservative, highest estimate). The OuterVision one seems much better than these.
• There are some other considerations to be made when getting this number: Do you overclock? Do you have 12 fans, two liquid pumps, and lots of LEDs? all of these things add power, so it's important to consider more than just the CPU and GPU even though these are the largest contributors.
  
  
• What is your use-case? Let's say you put your parts into PCPartPicker (here's a parts-list just to make an example) and it gives you a wattage breakdown showing 566W-max. Do you go buy a 600W (one notch above that) or do you 750? ? This is where use-case (like the overclocking question above) comes in. Do you leave your computer running F@H, crypto-mining, or other high-power workloads when you're not using it? There are multiple factors that can be considered here.
  • Let's say the highest workload for your machine is gaming and you don't overclock. Most of that workload goes to the GPU, usually the CPU isn't maxed out (sure, there are a couple exceptions). So even though your computer parts add up to 566W, you more than likely never draw close to that. So you could pick a supply rated at or just above your "max" (like a 600W) and be fine. Most of the time you're computer is at idle speeds and you'd probably occasionally get into the 300-350W range with spikes a little higher. A good rule of thumb is to go with one about 20% higher rated than your theoretical maximum load.
  • Let's say you overclock and water-cool and you play at p where your CPU is actually running heavily as well...you may need to add to those "stock-maximum" numbers. Do some digging into what other people see with their overclocked similar hardware. Maybe you expect your CPU to run at 280W regularly while the GPU is hitting 300W...you're still not doubling power numbers, but you may have more accessories (pumps, fans, etc.) to add in to the max as well. With this kind of use-case, it might make sense for you to step up from a 600W to a 650W-700W.
  • Now let's say you run something like F@H on your machine 24/7 (when you're not gaming) and you regularly max-out your power-load on your CPU and GPU (and thus your fans as well). You still aren't exceeding that 566W (other than extra fans, lighting, etc.), but you should think about the constant heat-load on the power supply. The hotter you run your parts, the earlier they degrade. So if running a constant heat-load for weeks/months at a time, you may want to inflate the max-power number more than other users just to reduce the heat-load so that you're not running it hot (and loud) all the time. In this rare situation, an 850-W wouldn't be ridiculous, because it would then run considerably cooler and quieter for you.
• Efficiency considerations (not efficiency ratings yet, but I wanted to bring up a topic I've seen about using the efficiency curve when it comes to selecting your power supply): There's a point often made about trying to plan for the highest point of a power supply's efficiency curve. While it is true that a power supply is not at it's most efficient operating point at maximum load, it's nowhere near the most important consideration. Here's an example of a titanium rated W power supply. It is most efficient in the ~250W-load region. If you were to make a decision on this factor alone, you would have to chose this supply for a computer that has an i5- and uses integrated graphics-only. You'd spend ~$250 on this titanium rated supply in the hopes of saving a dollar a month in energy bills? That just isn't going to be worth it. You can save some money here by not buying a supply considerably more powerful than you need.
  

2. Efficiency Ratings (Bronze, Gold, Platinum, etc.). Let's not get carried away.

• If you leave your PC on 24/7, you should care about getting the most efficient power supply you can afford (reasonably anyway). If you don't, it becomes considerably less important, with some caveats. The price differences can vary quite a bit from minimal differences between Gold/Platinum, to huge jumps. The price of Bronze (and I wouldn't even recommend buying one that has no rating) is usually much lower than Gold+, but those are generally for budget-builds.
  
  
• Here's an older thread that still has some good information. With respect to the efficiency rating itself, it's important to consider your use-case again and if you spend 80% of the computer's life-time at 20% power load, you should look at the efficiency numbers there when comparing two power supplies. For example, if PSU A is Gold-rated and PSU B is Platinum-rated, but PSU A is just as efficient at 20%, but drops below the requirement at 100% load, you're not benefiting by paying the price difference to buy the Platinum power supply. Because PSU A didn't meet the requirement at 100%, they can't call it Platinum, but it is just as efficient for your usage. The thread linked put some charts together to compare savings, but I think they assumed different power loads at constant-usage, so if you don't turn your computer on every day or all day, this may be a bit exaggerated.
  
  
• Your electricity costs where you live can make a difference. For most people, it would likely take years to make up the difference in price between Gold and Platinum or Titanium from the energy savings, but there are always exceptions and some countries/states/regions charge considerably more for every kWh and it can make it worth-while to go to a more efficient supply just because of the efficiency rating.
  
  
• Caveat: There's one primary system that power supply companies use to structure their product-stacks and that's the efficiency rating (outside of side-mount connectors, colors, lights, screens, etc.) as a general rule. What that means is that they probably put more bells and whistles (from a component-quality and circuit-topology perspective) into their Platinum power supply than they did their Gold or Bronze. So when you buy the Platinum supply, there's a chance that it also runs cooler and quieter than the Gold supply, as well as being more reliable in the long-term...but this isn't a guarantee. The only thing the "Platinum" or "Gold" ratings guarantee is efficiency ratings. While more-efficient circuits will result in less heat in the power supply, they're not always more reliable. I would say they have a tendency to be in this application, but definitely not always. Picking Bronze and below power supplies, however, can be a minefield. This is where companies really tend to cheap out on parts and while there are several out there that are surprisingly good quality, there are a huge assortment of really terrible power supplies at the $75 and under level that you have to watch out for. This gets us to the underlined, italicized, and bolded section below...

3. I know what power range and efficiency I'd like, now what?

• Here's where it gets a little interesting. Usually, your next step is going to be sort by budget, but you're also going to want to start narrowing down to specific models. You'll want to consider things like "How many devices do I need to power?" (less common question these days), "Do I plan to upgrade to a higher-powered GPU/CPU in the next couple years?", "Is color important to me?", "How big is my case and what cable lengths do I need based on where the power supply and other components are?"
  
  
• One thing that has made all of this simpler (even narrowing down on the power rating selection) is that ever since the GeForce RTX series launched (and /'s had huge current spikes that a lot of existing power supplies couldn't handle), a lot of new power supplies have launched. This has led to most newer model supplies having a much higher surge-current tolerance than older supplies. With older supplies, you would want to spend a lot more time looking into the power spikes of a GPU and then adding that to your max-power estimate of the system when picking a power supply rating just to make sure it wasn't going to trip and shut down on you mid-gaming-session. There were a few supplies that launched after that as new versions of existing supplies, but the RTX- series then launched with a new connector, spurring a full suite of new power supply models from every PSU-company. Newer power supplies with "ATX 3.x" and then later "PCIe 5.0" ratings started launching in droves. These more modern supplies usually have a 12VHPWR or 12V-2x6 output connector(s), 12V-2x6 being the newer and much safer version that are designed with cables that go directly to RTX-(+?) series cards. The more important feature though, is the specification requires that the power supply can handle twice the rated power to that video card for short durations. That's a simplification of the spec, but without making this post even long than it is, this has been a huge benefit to users in that power supply companies had to make up for the curve-ball of new GPUs drawing much higher current spikes than they did before and now we have more robust power supplies. What that means at the end of the days is you can buy a power supply that has a dedicated GPU-connector rated for 450 or 600W and it should undoubtedly handle that load (this rating changes based on supply and video card, so you need to make sure they match). You then just need to look at the rest of the components and make sure there's enough remaining headroom. Going back to that example before of the 566W computer, you could likely buy a 650W power supply like the be quiet! Pure Power 12M (just an example) that has a dedicated 450W PCIe 5.0 rated connector for the GPU.
  
  
• Think ahead! Power supplies can last a very long time compared to the rest of your components, especially if you buy a high-quality supply. Here's where instead of making the decision to buy just more power rating than you need, you buy something that can handle a big upgrade in the future. So you only need a 600-650W supply today, but you've got one of those nagging voices in the back of your head saying "Next year I'm buying a /RX-TX" (I'm guessing at model numbers for AMD, not sure what they're launching next gen yet) and you know that 6-18 months from now, you'll need more. The AMD RX series avoided the new connectors, but the RX and RX series still had higher power draw and current spikes than older system so the new specification still help even if you're not using that connector/cable (or using adaptors). If you don't want to replace the PSU at the same time you buy an upgrade-GPU, buy the bigger one now. I'd personally recommend a model that has a 600W-rated PCIe 5.0 connector(s) on it (like this SeaSonic VERTEX GX- for example) if you do intend to buy high-end GPUs in the future because we don't really know where the next gens are going to be limited and you may regret a 450W-limited one if you had your heart set on a / and they need more (let's see how smart/silly this recommendation is if the post is still here next year).
  
  
• The most important thing that you should do is READ REVIEWS. This cannot be over-stated. Things like the cultist-network tier list are a good reference, but not always complete. I like to recommend (once you've narrowed down to a few models) reading as many reviews as you can find. Look into a company's warranty and return policies, user experiences, and history. Some will surprise you, both positive and negative, so don't just assume that Brand X is always good or always bad. TPU also has a review databasethat shows their reviews as well as other ones their aware of for any power supply they've heard of (as well as other parts, but this thread is for PSUs). It even sorts by year, which can make it easier to find more recent reviews.
  • Things to look for in reviews as some are better than others: Did they do any tests? If so, how does the supply you're looking at compare to others in the same price/performance bracket? A site like Tweaktown might open a supply and tell you what parts are inside, but they don't have any data while TPU, Tom's Hardware, HWBusters, (and boy do I miss JonnyGuru.com and OklahomaWolf's reviews) might have some actual test data showing things like transient response, load regulation, ripple suppression, and vampire power. Sound and thermal levels might be important to you as well depending on preference and use-case.
  • A good review will go into depth about the regulator topologies used, but you don't need to be an EE or expert to understand what that means to you. Hopefully they explain if that particular topology is generally a good or a bad thing (and why), but usually the end result is that it impacts the efficiency (and thus heat inside the PSU), regulation quality, and sometimes noise (audible-noise). Often the fan is the loudest part of a power supply, but sometimes a really cheap poor quality power supply can have a noisy circuit that is very irritating. If the review shows you the difference between efficiency, regulation quality (for example), etc. of different supplies that you're comparing, that's the end result of those different circuit topologies and component-selection and why it's important.
  • Another place you can look if you really want to dig is reddit, Newegg reviews, and manufacturer forums. The EVGA G+/P+ series for example had really bad coil whine and there were several forum posts and user reviews around the internet describing how they seem to work alright, but they're quite loud and annoying. Newegg/Amazon reviews can be a minefield, but sometimes it is helpful to look for medium-to-bad reviews and see if there are any trends. This can be troublesome though, as a lot of times web-stores like this won't make a new page when a slightly newer model PSU comes out that fixed some problems with the previous version. There were several different variants of the Corsair Rx series for example and often the page would have a "()" with the model name or something, but reviews go back years before that...just bear that in mind when checking user reviews and they can still provide some good information.
  • The graph above of the Dark Power 13 efficiency came from a Cybenetics test report in their database. If they've looked at the supply and you want to do some deep dives into the data, those are pretty awesome.
    
• OEM Considerations. As mentioned above in the recommendation to read reviews and not just trust (or distrust) a brand entirely, OEMs play a role here too. The OEM is the company that actually makes the power supply (in this case) for the company who's brand-name is on the supply. As someone who spent a lot of time on EVGA's forum, I can use them as an example. They've used (at least) Super Flower, FSP, SeaSonic, and I believe ChannelWell as OEMs and even if you look at just the FSP-made supplies, some were good and some were bad. Leaving out which OEM was which, here are some examples: Original SuperNova G-series: pretty good, G2: great, G3: great, G5: bad, G6: good, G+: bad, G7: decent, P2: great, T2: great, P+: bad, P6: decent, etc. They had some really good supplies and some fairly bad supplies, all at the "high-end" of their product-stack, some on each side of the scale from the same OEM. So the responsibility lies with you to read reviews and try to find out if that particular supply your considering is well-made.

--Let me walk start to finish through an example, just to cut through the wall of text and show what I mean:
1. I put my components (not including my custom water loop) into PCPartPicker and came up with ~877W. Some considerations: I have two D5 pumps, 13 fans, two LED strips, and probably a device or two I'm forgetting, plus I like to overclock...so there's a chance that I run my GPU up to ~600W and my CPU at 300W (well, I've seen more, but not at the same time as the GPU was maxed out...and in normal gaming scenarios it's more like 115W, but I probably didn't have all these numbers before-hand, so you can only go on best-guestimates), so I want to be perfectly stable, quiet, and cool while pulling 950W. Is it going to do that all the time? NOOO, but I'm an engineer and I'm programmed to think worst-case, so I'm going to pick a supply based on that. Burt Gummer once said "when you need it and don't have it, you sing a different tune." That said, nothing I'm doing justifies a -W power supply. I could probably use a W that is rated to the new ATX 3.0 specs and be just fine, but I'm also going to open myself up to W so I'm never even being that hard on it (and it runs super cool).

2. I don't leave it on 24/7. I game with modern games and do some overclocking benchmarks for fun, so it has to meet my power requirements from #1, but I'm not going to notice any efficiency differences between Gold/Platinum. That said, I want it to be reliable and last a long time, so knowing the PSU companies only put the top quality parts in Gold+ power supplies, I want to buy at least a Gold-rated supply. I'm open to Platinum+, but I don't think I need it.

3. I'm probably not going to buy any parts significantly more power-hungry than these very power-hungry (sometimes) parts, I don't have a brand preference, but I do want to weed out completely unknowns...let's go through some of the PCPartPicker filters (which can also be done just as easily on sites like Newegg, Amazon, Micro-Center, Best Buy, etc., but most people all over the world seem to be able to use PCPartPicker, so I'll just stick with that for this example):

• Efficiency: Gold, Platinum, Titanium
• Wattage: -
• PCIE 12+4-pin 12VHPWR Connectors: 1-4
• Because I do have some personal preference here, I'll narrow down brands to: Asus, be quiet!, Corsair, SeaSonic, Super Flower, and Thermaltake. This is subjective and if you don't already have experience or preferences here, leave it open to all and read reviews. There are some good supplies from Gigabyte, MSI, Antec, and others for example, but I just wanted to narrow it down for this.

If I sort by ratings, the top choices are: SeaSonic VERTEX GX- ($194), be quiet! Straight Power 12 ($199, the supply I actually own, look at that), Corsair RMe (, $159), Asus TUF Gaming G ($149), and Thermaltake Toughpower GF A3 ($164). I see a couple down towards the bottom that I've read great reviews for, but there are no ratings posted on PCPartpicker, so there are always going to be flaws just going from one site. At this point, I'd go through the ones on this list that fit the rest of my requirements for price/performance, cable lengths, color, etc. and start reading reviews. Based on when I purchased mine, I don't think the SeaSonic or Asus was available (not many with dedicated PCIE 5.0 connectors were at the time I bought mine), but this is where it gets subjective and you have to decide from the reviews you can find what pros and cons are most important to you. the be quiet! one fit my case/build well, had cables that look nice, and I've had great experiences in recent times with that company for other parts, so based on reading some great reviews for that power supply, I went for it (my first PSU from them) and it has been great so far. I don't know 100% certain that it's running cool because there are no exposed sensors and it's buried in there, but I can't hear it ever so I can only assume based on the fan never spinning up much that it's got a pretty easy life in there. I did end up with a Platinum supply (I would have happily looked at more Gold-rated supplies if they were available at the time), and it has a 10 year warranty, so a high-end supply like this should last me a long time.​​​
Just to add a closing thoughts and general information section...I don't write many posts like this, so I'm sorry if it was a bit rambling or not formatted as well as it would be by the folks who put out more big threads. I also wrote it in chunks in between other tasks so I had to keep coming back to it, proofing, editing, etc. I used several different power supplies as reference examples, but I didn't do that to recommend those supplies specifically, I just picked some supplies I'm a bit familiar with for one reason or another that had information or features pertinent to the discussion topic. We all have our favorites. My personal computer is not a budget build (obviously) so that list of brands I narrowed down to in my example is reflective of that. For example, I was trying to help someone on here find something for a build they were working on recently and ended up recommending a white Gigabyte power supply because it was just barely within their budget, they required a white power supply, and the reviews were good for that particular model.

If you've read this whole thing, please provide some feedback. I'm all for constructive criticism, so feel free.