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Last Updated: April 21, 2021
Choosing the best PSU for your gaming PC build can be super confusing. To the untrained eye, looking at and comparing power supply specs is basically trying to decode alien language, and the clever marketing used by this and that company trying to convince you that their PSU is great doesn't make things easier.
Then there's the conflicting advice you'll find online from fellow gamers and PC users, with some perhaps recommending you simply buy the cheapest PSU you can find to save money, and others who swear anything but buying the most expensive, absolute best power supply on the market will have your new system imploding within the week.
Like a lot of things in life, the truth is somewhere in the middle, and what you should do (read: how much you spend on a PSU) depends entirely on your specific PC build. If you're building a high-end gaming PC with one of the best graphics cards on the market such as a NVidia GeForce RTX 3080 or AMD Radeon RX 6800 XT, sticking to the best PSUs on the market (or thereabouts) is definitely wise. Providing systems that house powerful graphics cards and CPUs with enough clean, stable power from a quality, reliable, efficient power supply is important for the longevity and stable operation of your new beast.
For less powerful yet still capable gaming PCs, you don't necessarily need the best PSU out there, though you still want to remain above a certain level of quality to reliably power your system for many years to come. For the cheaper entry-level gaming PC builds on a tight budget, your PSU requirements aren't as stringent, but that doesn't mean you should rush out and buy that cheap no-name PSU. A golden rule of PC building you'll often hear within DIY circles is to never go too cheap on your PSU, and that saving a few bucks on that enticingly lower-priced yet potentially lower-quality unit may end up biting you later on.
Related: How to Install a PSU (& Which Way to Face)
Average or straight-up bad power supplies can cause all sorts of headaches down the road, such as buckling when under load (eg crashing your PC mid-game), providing less power in practice than what was listed on the spec sheet (eg a poor quality 650 watt PSU may turn out to fail at providing that amount of wattage), operating at less than desirable efficiency levels, running with loud noise all the time, or even worse such as prematurely dying on you which has the potential to damage all your other PC parts.
In this guide I'll not only roundup my current top PSU recommendations for various budgets as someone who has payed relatively close attention to this sub-niche of DIY PCs for many years, but we'll also cover all the important basics of choosing good PSUs including what the important specs actually mean in plain English, so that you can be a much savvier shopper for the rest of your DIY days.
Top 4 Best PSUs for Gaming PCs (2021)
1. Seasonic PRIME TX-1000 (Best PSU for RTX 3090)
2. Corsair RM850x (Best PSU for RTX 3080/RX 6800 XT)
3. SuperFlower Leadex III 750 (Best PSU for RTX 3070)
Check Price: TX-1000 (most flexible), TX-850 (if no future GPU upgrade)
Honorable Mentions: HX1000, RM1000x, Supernova 1000 P2, Supernova 850 P2
Definitely not for everyone, but if you simply want the absolute best power supply money can buy right now for a powerful RTX 3090 build, the Seasonic Prime TX-1000 is definitely a candidate for that crown. Seasonic are well known as a leader in the PSU market in regards to quality and reliability, and the stellar reviews from reputable sources along with a standout super-long 12 year warranty prove the TX-1000 model to be one of their very best.
It's also both power and heat efficient, meaning lower power bills over the long haul and low noise, but most importantly it delivers very clean and stable power suitable for even the most demanding of use cases such as multi-GPU and heavy overclocking. There's a 1000, 850, and even a 750 watt model within the TX series, but if building a RTX 3090 system you're best off with the 850 or 1000 watt variant for some healthy headroom, and if overclocking or planning on significant upgrades to your system in future, I would stick with the 1000w model.
Also, you don't need a cream of the crop, top of the line premium (and expensive) PSU like this - even for a beast of a GPU like a RTX 3090 or RX 6900 XT - but it could be a worthy investment if you have high demands and want the most reliable unit possible. For most people though (again, even for the super powerful RTX 3090), I recommend the slightly more cost-effective RMX series below which is still a tier A unit.
Seasonic PRIME TX-1000 Specs
Power: 1000 Watts
Modular? Yes (Fully)
Warranty: 12 Years
Efficiency: 80 Plus Titanium Certified
Size: ATX (Standard)
Full Specs: Seasonic
Check Price: RM850x (most flexible), RM750x (no future GPU upgrade)
Honorable Mentions: Supernova G3 850, SuperNOVA G3 750, Leadex III 850
The RMX series are among the best power supplies out there today, and one of Corsair's best offerings. Corsair have a mix of great, good, and average PSUs, but the RMX is unquestionably a tier A unit no matter the metric used. For strong graphics cards like the RTX 3080 or RX 6800 XT, combined with top CPUs like a Ryzen 7/9 or Intel Core i7/i9, you want a capable, reliable, quality PSU, and this one won't disappoint in those regards.
The downside is they don't come cheap, but it's a worthy investment in my opinion if building a powerful RTX 3080 system (or equivalent). The RMX is also perfectly suitable for even a RTX 3090 should the aforementioned Seasonic TX series be out of your price range. Don't make the mistake of confusing the RMX series with the similarly named RM series (without the 'x'), as the latter is a slightly inferior unit (though still of good quality).
The RMX comes in 550, 650, 750, and 850 watt models, but the 850 watt model is more than enough in terms of wattage for even the super power-hungry RTX 3090. If you get a RTX 3080 or RX 6800/XT and are certain you won't be upgrading your graphics card over the lifetime of your system, a 750 watt model will suffice if you want to save a bit of money, though these latest RTX 3000 cards are notoriously demanding on PSUs and for maximum reliability, stability, and peace of mind, I recommend an 850w unit.
With 750w, you're unlikely to have issues with a RTX 3080, though you have less headroom. For less powerful graphics cards, the 550 watt or 650 watt RMX model would also be great if you want to invest in a top-tier PSU, though there are better overall value models in that case (less demanding GPUs are fine to pair with mid-tier PSUs instead of A-class ones like the RMX). A good alternative to the pricey RMX series (quality doesn't come cheap) would be the EVGA Supernova G3 (or G2 series if you can find it), which are also excellent, well-reviewed, top-rated power supplies for a gaming PC that I would put just behind the RMX series overall.
You can sometimes find these cheaper than the RMX, so if that's the case in your region at the time of you buying, definitely consider them instead. They are neck and neck in terms of quality, reliability, and features, though the RMX is still technically better for its typically quieter operation (less noise). Yet another great option would be the 850 watt SuperFlower Leadex III Gold, another top-tier unit.
Corsair RM850x Specs
Power: 850 Watts
Modular? Yes (Fully)
Warranty: 10 Years
Efficiency: 80 Plus Gold Certified
Size: ATX (Standard)
Full Specs: Corsair
Check Price: 750 Watt (most flexible), 650 Watt
Honorable Mentions: SuperNOVA G3 650, RM650x
For a gaming PC build with a NVidia GeForce RTX 3070 or similar GPUs like a AMD Radeon RX 6800 or RX 6700 XT, a good quality 650 watt power supply is actually enough, but for maximum future flexibility I suggest a 750 watt model as it gives you much more headroom to be able to upgrade your graphics card in a few years.
Lesser known to the masses, SuperFlower are a very well respected PSU manufacturer who have made top quality units for other companies like EVGA in the past. EVGA and SuperFlower parted ways recently, and now the latter are selling their units direct to the US market. This recent entry into the direct-to-consumer business is the reason why SuperFlower isn't as well known in the PSU market compared to companies like Corsair, Seasonic, and EVGA (at least for now), but don't be fooled as they are some of the best quality PSUs on the market without a doubt.
Only reason I've listed it here as the best "value" high-end PSU is because it's typically cheaper than the more well known names like EVGA and Corsair, but make no mistake, SuperFlower power supplies, and specifically their higher quality models like the Leadex III Gold series, are as good if not even better in some instances. The Leadex III Gold is highly recommended, whether you opt for the 750 or 850 watt model. SuperFlower also have a Bronze-rated range which are good value budget-oriented models for less powerful builds that I can also highly recommend.
See Also: Best GPUs for Gaming Based on Budget
SuperFlower Leadex III Gold Specs
Power: 750 Watts
Modular? Yes (Fully)
Warranty: 10 Years
Efficiency: 80 Plus Gold Certified
Size: ATX (Standard)
Full Specs: SuperFlower
Check Price: 650 Watts (most flexible), 550 Watts (no future GPU upgrade)
Honorable Mentions: EVGA 500 BQ, Pure Power 11 600, Focus GX-550
For mid range GPUs like a RTX 3060 Ti, standard RTX 3060, or similar-performing AMD cards (RX 6700 XT and RX 6600 XT), a decent 650 watt power supply is your best bet. Again, you can get away with less power such as 550 watts, but having that extra headroom is ideal to keep your options open for future upgrades such as upgrading your GPU in a few years. When building a PC around these more "bang for buck" mid-tier graphics cards, you also want the other components in your system to be good-value picks as well, meaning not overspending on pricey components you perhaps don't need.
In other words, for most people there's no real point pairing a mid-range GPU with an absolute top-tier, expensive power supply. Nobody wants to do that because it kind of defeats the purpose of getting a value-oriented GPU. Don't get me wrong, the RTX 3060/Ti is no slouch, and still plenty of firepower for even decent VR performance as well as regular flatscreen 1440p/1080p (and respectable 4K performance in certain games).
So, when it comes to choosing a power supply, the trick is finding a good value model, but importantly simultaneously ensuring you pick one of good enough quality. Rule number one of buying a PSU is to avoid lower-quality units at all costs, as the few dollars it might save you upfront can come back to haunt you later on if your PSU has issues. Mid-range GPUs aren't as demanding and reliant on having a high quality PSU that provides clean, stable power, but they still need a decent PSU if you care about your system running nice and stable, and lasting the distance.
So, to balance price vs quality, out of all the PSUs on the market right now my top pick is the Corsair CXM series, a frequent inclusion in the best gaming PC builds series. The CXM has stood the test of time as one of the better value oriented models out there, that is normally very affordable compared to higher-quality tier A units but that importantly doesn't sacrifice on quality too much. Just don't go pairing the CX650M with a RTX 3080 or something like that, as you definitely want something a little better for such a demanding card. For lesser cards though, it's a great budget PSU.
Just be aware the older CX models from Corsair of a few years ago actually had different, lower quality internals, making them only suitable for low-powered entry-level gaming systems, but the modern day CXM units that were re-introduced to the market in recent years are much better. Anyway, I can highly recommend either the CX650M, CX550M, or even the CX450M depending on the specific graphics card and other components you'll be including your setup (and depending on how much headroom you want for future upgrades).
Corsair CX650M Specs
Power: 650 Watts
Modular? Yes (Semi Modular)
Warranty: 5 Years
Efficiency: 80 Plus Bronze Certified
Size: ATX (Standard)
Full Specs: Corsair
If you don't have time to read this whole FAQ (it's pretty long as I've tried to make this guide as comprehensive as I can), just read this section to get a quick overview of what to look for when choosing a good power supply for your new gaming system.
The PSU is an often-overlooked part of a gaming computer, but it makes sense that many newcomers to PCs and/or DIY assume that it isn't an important component to think about.
“It’s just a power supply. I’ll buy the cheapest I can find to save money”
Such thinking could come back to haunt you later, as you could say that a computer is only as strong as its weakest link. Building a decent gaming PC with a bad power supply is a recipe for disaster over the coming months or years, especially if you're using a high-end graphics card and doing a lot of gaming or other demanding workloads.
While a power supply won't directly affect gaming performance, and in many cases (pun intended) there's no need to buy a top of the line premium PSU, if you want a reliable PC over the long haul that won't fail prematurely and/or put your other expensive components at risk, there's a certain baseline of quality you should stick to when choosing a power supply. Besides failing on you, lower quality power supplies have other downsides such as typically lower efficiency levels leading to higher power bills, poor heat efficiency leading to higher noise and the potential to crash your system when under load, and some PSUs have bare cabling which can even leak RF energy (not good).
Gaming computers vary greatly in power and performance, so the amount of PSU wattage you need can vary greatly too. Modern gaming desktops can require a PSU with a wattage of anywhere between 450 watts to 1000 watts. On average, for a typical mid-range gaming PC you'll likely need around 550 to 750 watts, with numbers less or more than that being for either super cheap budget PCs or extreme systems.
You don't want to simply guess your power supply wattage requirements though, so when planning a PC build you need to calculate roughly how much power your full list of parts will require (and don't forget accessories like hard drives and extra case fans). You then want to choose a PSU that has slightly more wattage than what you need.
So, if your parts list requires around 400 watts, then get a 500-550 watt unit to be safe, or even 600 watts if you'll potentially be doing solid upgrades to your build in future (such as upgrading the GPU, which can change your PSU requirements considerably). If you'll be overclocking your gaming computer, whether your CPU or GPU (either can be overclocked if you're wondering), you will also need to keep that in mind when choosing a PSU as overclocking will use more power.
Thankfully, there are online tools that make estimating the power consumption of your PC build easy. PCPartPicker's built-in wattage estimation is the most popular; simply select all the parts you're thinking of building, and it will show you an estimated wattage. From that number add on 100 or more watts depending on how much power headroom you want based on your usage and/or upgrade plans. There are other tools out there as well, such as the Outervision Power Supply Calculator, but PCPartPicker is the easiest and most user-friendly.
Another spec you may need to be aware of when choosing a power supply is its physical size, technically called the form factor. However, most power supplies on the market are of the same size - the ATX form factor (technically ATX12V) - which will fit in any ATX or microATX computer case (which covers the far majority of gaming computer cases on the market). For the most part, the only time you need to be concerned about the size of a power supply is when building in a very small mITX case, as some mITX cases require what's referred to as a SFX power supply. However, some mITX cases can fit an ATX PSU, so you don't necessarily need a SFX power supply for a mITX case. Always check the case specs.
Lastly, whilst unimportant for the majority of PC builds (so feel free to ignore this bit), sometimes the depth of a PSU is different. In other words, while the width, height, and screw placement is the same as other PSUs of the same form factor (eg ATX), the depth of that particular unit may be longer than usual. PSUs are typically 6 inches in depth, but certain powerful PSUs with high wattages may be deeper. If you want to be extra cautious that a certain large, beefy PSU will be compatible with a certain case (especially if said case is fairly compact in the length department), you may want to check if that case lists a spec related to PSU depth and check it against your PSU's depth. In the far majority of situations, you don't need to do this though, and any ATX PSU will fit in any ATX/mATX case.
Power supplies can be either modular, semi modular, or non-modular. A modular power supply (sometimes referred to as "fully modular") is one that has detachable power cables that allows you to remove certain connectors that you don't need to use for your PC. The benefit of this is having less cable clutter within your finished system, and specifically more freed-up space within the bottom of your case (where power supplies are installed in almost all modern PC cases) since you can detach any power cables that you won't need to use (such as extra SATA or PCIe power cables).
Modular power supplies can also make installation a little easier, especially in smaller cases, as well as making power supply cable management a bit simpler (less cables to manage). Furthermore, the extra room within the bottom of your case afforded by a modular PSU may also lead to slightly better airflow within your system (and perhaps less dust build-up).
All of this sounds great, so why would you not buy a modular PSU? Price - modular PSUs cost a little more than semi-modular and non-modular PSUs, though not necessarily all that much (sometimes a modular model can only cost 10 to 20 dollars more than a same/similar non-modular unit). Whether or not you should spend the extra money on a modular PSU is down to personal preference and your particular PC build.
If you're on a budget, non-modular PSUs may be the way to go if you want to save as much money as possible, especially if working in a roomy mid-tower or larger. In general, the smaller the case the more convenient having a modular PSU will be. If budget isn't a big concern and you want the easiest, most flexible solution, stick to modular PSUs.
Semi-modular PSUs are also a great option, and not much different to modular (ie fully modular) PSUs. Semi-modular PSUs have a few cables that can be attached as needed (and detached if not needed), but also some permanently attached cables like the main motherboard and CPU connectors (which you would never need to detach anyway).
Power supplies have various efficiency levels which is one measure of how good a particular unit is. More efficient PSUs not only draw less power, meaning lower energy bills, but they produce less heat and therefore less noise as well. The efficiency of a power supply is given a rating, with "80 Plus" being the bare minimum rating you should go for. Meaning, if a unit doesn't have "80 Plus" mentioned somewhere then chances are you should avoid it.
There are always exceptions to the rule though, but in general opt for a 80 Plus unit or better whenever you can. There are levels to 80 Plus ratings, with basic 80 Plus, then 80 Plus Bronze, Silver, Gold, and Platinum, in order from least to most efficient. For super powerful gaming computers you'll want a gold rated PSU or better for maximum efficiency.
Another thing you may need to consider when choosing a power supply are the power connectors, as different units come with different types and amounts of cables. For most gaming PC builds, if you buy a good-quality, popular PSU and your build is a pretty standard modern setup without much extra add-ons, chances are you don't have to worry about checking the PSU connections. But for more advanced and/or higher-end builds, or if you just want to be extra safe, it's something you'll want to double check.
First of all, all computer power supplies will have either a 24 or 20+4 pin main motherboard connector, and either a 4 or 8 pin 12V connector, both of which connect to the motherboard. But what you'll want to check is that your PSU has the right type and amount of power connectors for your graphics card - if your card requires dedicated power (most mid to high-end GPUs do). Some GPUs will require just 1 PCIe 6 or 8 pin cable, while others may need 2 of these. Most modern PSUs will come with 2 6+2 PCIe cables though (which can connect to either a 6 or 8 pin GPU connector), so you should be good, but if your GPU needs 2 of these PCIe connectors then be sure your PSU does indeed have 2 PCIe connectors.
For advanced users, if you’re running multiple cards in SLI or CrossFire you'll want to also confirm your PSU is either SLI or CrossFire compatible as not all are. It should specifically be listed in the PSU specs, but keep in mind some units won’t officially list support for SLI/CrossFire but are still capable of powering multi-GPU setups (in which case you'll need to dig a bit deeper to find out if your PSU is good to go for this).
If you have a ton of accessories for your PC build, check that your PSU has enough SATA or Molex 4pin connectors for your hard drives, optical drives, and other devices like case fans (which may actually require those older Molex connectors). Most modern PSUs will come with plenty, but you never know if you have a lot of components to hook up. Lastly, if you just arrived in a time machine from 10,000 years ago and you're including a floppy disk drive in your new build, check your PSU has such a connector as floppy drives require their own type of PSU cable.
See Also: How to Connect PSU Cables (& Cable Management)
Choosing a good PSU isn't solely about selecting by brand and brand alone, as companies produce and/or sell different models that can vary in quality (sometimes quite significantly). However, there are certain PSU brands that consistently offer top-notch, reliable models, and have stood the test of time. The following are some of the best PSU brands you can mostly trust on the current US market, but still do your research on the specific model/s you're considering:
Doesn't mean you shouldn't buy a PSU from a brand that's not on this list, as the above names simply represent the very best PSU brands overall based on their track record over the past few years (and based on my opinion). You'll find some decent PSUs from other companies like Gigabyte, Thermaltake, and Cooler Master just to name a few that come to mind, but you'll find plenty of PSU models to avoid from these and other PSU brands that I didn't mention in the exclusive list above. Also, it's worth repeating as well that not ALL power supplies from the list above are great, as most of them produce a variety of units that range in quality. Choosing a good PSU is not just about brand but also about researching and comparing specific models.
This is a more advanced topic, hence why I've left it to last, so don't feel like you need to understand PSU rails in order to choose a power supply for your build. It can be handy to know though, especially when deciding between different high-end power supplies for a powerful high-end rig. Power supplies are made up of different "rails" that transfer power from the PSU to your components, with the most important to know about being the 12V rail which is the one that provides power to your most powerful parts (including the CPU and GPU).
In a typical gaming computer the graphics card will require the most power, and so you’ll want to get a PSU that has at least 24A (amps) on the 12V rail if you have a single mid to high end GPU, and at least 34A for a high-end multi GPU NVidia SLI build. These are general guidelines, so if you want to be super prudent about your PSU choice it's best to find out exactly what your particular GPU will require.
There are basically two different types of PSUs out there (in regards to its rails). Single rail, and dual/multi-rail PSUs. Single rail units have a single high-powered 12V rail to power all your parts, while PSUs with multiple rails have more than one 12V rail each with different amperages to divide power between two or more rails.
Whether a unit has single or multiple rails doesn’t affect its overall performance, and if your build only requires a lower-power PSU such as 550 watts or less, the single vs dual rail PSU issue does not matter and either will be fine (so long as you still pick a decent quality PSU).
But for power users, a multi rail power supply will offer an extra layer of protection in case there's a short circuit, and when you start heading into enthusiast and real high-performance PC territory that use huge 1000 watt PSUs or higher, multi-rail PSUs start to become a whole lot more crucial as it's risky and dangerous to output so much power on only the single rail.
VPN software is quite important in this day and age and will improve the security and privacy of your PC when online. There are also benefits to using VPNs for gaming.
There's lots of VPNs out there but the ones I recommend most to gamers is ExpressVPN (special link that gets you 3 months off. they also offer a free trial here) and NordVPN which are both highly rated gaming VPNs because they're the fastest and most secure.
Indie game dev currently working on my first public release after years of hobby projects, a story-driven VR FPS built with Unreal Engine (to be announced soon here for anyone into VR FPS's). Also likes writing about tech, which also helps fund development of the game.
My favs of all time are OOT, Perfect Dark, MGS1, MGS2, GE007, DKC2, THPS3, HL1, and HL2, with the most recent addition to my list of immortals being the VR masterpiece Alyx. If you want help with a new build feel free to ask on the main PC builds guide. If you found the site extra helpful and wish to support the work I do here, sharing an article with a friend helps a lot and is much appreciated. - Jules