Your power supply (or PSU) plays a major part in determining your system's reliability, depending on its overall performance. So you should be careful when it comes to picking the right PSU for your needs. A great power supply should also have protection features to save your components (including the power supply itself) should something go wrong with your electricity supply or your PC components.
You’ll also obviously have different concerns and needs depending on whether your power supply will be pushing a monster mining rig, an always-in-demand workstation, or a mainstream productivity or gaming desktop. We’ll help you find the right PSU for your next rig—whatever it might be—below.
Why Trust Us?
Tom's Hardware has been reviewing PC hardware for overr two decades. We put each power supply through a gauntlet of tests that measure everything from load regulation to power efficiency, plus key protection features and much more. We've tested hundreds of units, from sub-$50 (£40) budget models to 1600-watt PSUs with top-of-the-line components and features. So we can separate the best from the unreliable and inefficient models that aren’t worth risking your precious components on.
Quick Shopping Tips
First, figure out your wattage requirements. It doesn’t make sense to buy way more potential power than you’ll ever use. You can roughly calculate how much power your new or upgraded system will draw from the wall and look for a capacity point that satisfies your demands. Several power supply sellers have calculators that will give you a rough estimate of your system's power needs. You can find a few below:
You probably don’t need a 1,000-watt PSU, even for an extreme gaming rig. A few years ago, all graphics cards on the high-end of the GPU hierarchy were very power-hungry. But this changed with Nvidia's recent architectures. It's simply not necessary to buy a 1kW PSU for a couple of RTX 2080s. An 800W model will do just fine, leaving headroom for an overclocked CPU as well. Fans of AMD's flagship Vega cards or the newer Radeon VII will need to plan for higher power use, pairing these cards with PSUs featuring greater maximum output.
Check the physical dimensions of your case before buying. Chances are, if you have a standard ATX PC case, an ATX power supply will fit. But many higher-wattage PSUs are longer than the typical 5.5 inches. So you’ll want to be sure of your case’s PSU clearance. If you have a particularly tiny or slim PC case, it may require a less-typical (and more compact) SFX power supply. We have picks for this form factor below as well.
Want a clean build or working in a tiny case? Consider a modular power supply. If your case has lots of room behind the motherboard, or your chassis doesn’t have a window or glass side, you can of course cable-wrap the wires you don’t need and stash them inside your rig. But if the system you’re building doesn’t have space for this, or there’s no easy place to hide your cable mess, it’s worth paying extra for a modular power supply. Modular PSUs let you only plug in the power cables you need and leave the rest in the box.
Model Comparisons: Overall Performance and Performance Per Dollar
In the relative performance charts provided with each one of our PSU reviews, we create an index of sorts that encapsulates overall performance, including load regulation, ripple suppression, efficiency, hold-up time and the maximum power each PSU can deliver. This should make your life easier, since you won't have to decipher several data-heavy graphs to reach your own conclusions.
|Relative Performance||Performance Per Dollar|
You only need to take a quick look at our index above (left) to see where your PSU of choice stands against its competition. The second-most-important chart (on the right above), derived from the relative performance score, is performance per dollar. This should also help you when shopping for an upgrade.
Best Cheap PSU ($60/£60 or less)
Best PSU: Up to 550 Watts
Best PSU: Up to 650 Watts
Best PSU: Up to 750 Watts
Best PSU: Up to 1,000 Watts
Best PSU: Above 1,000 Watts
Best SFX PSU
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