Whether you’re buying a new power supply, or are just curious about how much electricity your PC uses, an online power supply calculator can help.
These handy web tools work out the combined power requirements of your components, so you can make an informed decision about the wattage you need. Here are some of the best power supply calculators around.
Why Use an Online Power Supply Calculator?
Every component you add to a PC will draw electricity from the power supply unit (PSU). The more you add, the more power you need. RAM, graphics cards, processors, motherboards—they all need juice to run effectively and safely. This only increases if you start overclocking your components.
If your PSU is too weak to power all your components, you can quickly run into problems. Your PC may not start, it could suffer seemingly random shutdowns, and your operating system could freeze. If you’re particularly unlucky, it might burn out, taking your motherboard and components with it.
Online power supply calculators can help you avoid such issues. They’re not 100 percent accurate, but they can indicate if your power supply is obviously insufficient or running at close to capacity. It’s important to remember, however, there are other factors you should consider when choosing a PSU. Cheap PSUs often supply less power than they claim and may be less reliable.
1.OuterVision Power Supply Calculator
The main focus of the Extreme OuterVision website is the PSU calculator, but it also provides power supply reviews and example builds for different purposes. The power supply calculator can be set to either Basic or Expert.
Like other PSU calculators, you choose your components using a variety of dropdown menus, sliders, and text boxes. The Expert version expands the number of these to include advanced settings, like overclocking and liquid cooling.
In either case, you can set how long your PC will run every day, and how much of that time will be spent on high-demand tasks like gaming or 3D rendering. In both modes, you can only set the motherboard option to Server, Desktop, or Mini-ITX.
Most of the fields only allow for generic components, like 8GB DDR4 RAM or 256GB SATA SSD. However, you can choose specific processors and graphics cards, which presumably means more accurate results.This is the only calculator in this list that includes monitors.
The results include load wattage and recommended wattage. In Expert mode, you can also see combined amperage and an estimate of your energy costs. The OuterVision site also features a power consumption calculator for cryptocurrency mining rigs.
As well as working out the potential mining profitability of your rig, it links to Amazon, where you can buy the parts to build it.
2.Cooler Master Power Supply Calculator
Most tech enthusiasts know Cooler Master. It makes a wide range of cases, coolers, power supplies, and peripherals for PC builders.
If you’re building a straightforward PC without a lot of extra bells and whistles, Cooler Master’s PSU calculator can give you a reasonable estimate of your power requirements.
It offers a choice of seven motherboard form factors, including ATX and Mini-ATX, but not specific board models. You can set your particular processor and graphics card too, but everything else is generic.
It doesn’t offer anywhere near as many options as the OuterVision calculator, but it does cover the basics well enough. And, of course, this calculator exists as a way to recommend Cooler Master power supplies. Cooler Master is widely considered a trusted and reliable brand for PSUs, but it's important to recognize that bias.
3.Be Quiet! PSU Calculator
Like Cooler Master, Be Quiet makes cases, PSUs, fans, and other PC parts, so its calculator naturally recommends its own products. Its PSU calculator is similarly stripped-back, but it has some interesting options that make it worth a look.
As with other calculators, the only areas you can fill with specific models are for the processor and graphics card. It doesn’t have options for the motherboard at all, and you can only specify a quantity of SATA disks, PATA disks, and RAM sticks—not their speed or capacity.
It also has some simple overclocking options (overclocked or heavily overclocked), as well as a setting for USB 3.2 power transmission. But what stands out is the ability to save configurations to your PC as text files. This may not be that useful with such a relatively simple calculator, but it’s nice to have the option.
Once you’ve made a calculation, the site will offer you a selection of Be Quiet power supplies, with options to filter the results further.
4.Power Supply Calculator
This PSU calculator is best for older computers, since it doesn't appear to have been updated for a while. It's missing a lot of newer components, but it also allows you to add FireWire connections to your specification, which you may not find with new calculators.
Also worth noting is the bar chart it produces at the end. This shows you the distribution of power throughout your system, both when idling and when under load. This isn't something most other calculators offer.
Along withusual components like hard drives and SSDs, you can add peripherals such as keyboards and mice. You can also include a variety of PCI and PCI Express cards, and up to five fans. There are some overclocking sliders for processors too.
If you have an older PC and want to check its energy consumption or replace its PSU, this calculator is worth trying. It offers some interesting results you won’t find anywhere else, and it doesn’t push you to buy anything. For new PCs, though, you will need to use one of the other calculators.
5. PCPartPicker System Builder
PCPartPicker presents you with a list of all the essential components you need to build a PC. Under each heading is a button, which you click to add a part. You then get a long list of actual products to choose from, including prices from various merchants.
As you add parts to your list, the System Builder keeps track of the compatibility of your components and the overall estimated wattage. You also have the option of exporting your list. The site automatically generates a unique link you can share, but you can also generate markup text that you can copy and paste to embed elsewhere.
Your lists can also be saved to your account if you create one. Plus, you can see a history of all the lists you’ve made, which is perfect if you want to compare potential builds.
It’s not a dedicated PSU calculator, so it doesn’t give you a breakdown of energy requirements, and doesn't take overclocking into account. But it does allow you to choose actual components for every part of your build and then base the PSU requirements on that.
How Accurate Are Power Supply Calculators?
PSU calculators can only give an estimate, rather than an exact figure. Therefore, you can use them as a guide, but don’t take the results as gospel.
In our tests, weimagined a gaming PC witha high-end graphics card and processor, 16GB of DDR4, aSATA SSD, and a 7200rpm hard drive. The recommendations we got from the calculators ranged from 527W to 580W.
In all cases, those figures were lower than expected. Nvidia, for example, states a high-end cardlike the GeForce RTX 3080 requires at least a 750W PSU.
Get the Right Amount of Power to Your Rig
Indeed, it’s best to have some overhead when choosing a power supply, so whatever these calculators suggest, you should probably add a couple of hundred watts on top. They seem to all be guilty of suggesting the bare minimum.
Remember, too, that not all power supplies are created equal. Cheap or underpoweredPSUs can cause all kinds of problems. In fact, they can even completely fry your motherboard. So choose carefully, and seek advice from an experienced PC builder if you’re unsure.
