The power supply is the beating heart of your gaming PC, the part that distributes the vital life of energy around your expensive processor, motherboard, and graphics card. Your power supply can set the limits of your ambitions when it comes to potential PC upgrades, so it’s always worth keeping an eye on the future when it comes to choosing your next power source.
First you have to determine how many watts your system or potential system is consuming and on top of that you have to leave enough room for future upgrades. Moreover, you should keep in mind that a nice efficiency location is usually around 40-50% of the maximum rated capacity of the PSU. This and the closest given power source is to the maximum output load, and the lowest efficiency.
So, if your system needs 500W at full load, it is not wise to have a 550W PSU but at least 650W. However, most of us wouldn’t stress our systems around the clock unless you have time to play games constantly. Games can tax your PSU because they will fully load your graphics card, which is probably the thirstier part of your setup.
To get an idea of what your system or upgrade dream will look like, in terms of power draw, you can easily enter all the details into a handy PSU calculator. We like to use OuterVision’s external power supply calculator, but there are other programs available.
The most accurate way to determine your system’s power needs is to use a kill-a-watt and take some readings under full load, this is useful if you want to replace your existing PSU. Note that this procedure will only give you an indicative reading as it does not take into account the efficiency of your PSU.
The most power-demanding parts of today’s systems are the graphics processing units (GPUs) that are followed by the central processing units (CPUs). Unfortunately, manufacturers don’t provide clear information on the actual GPU power consumption, and to make matters worse you also have to consider potential power spikes that could restart the system if the PSU isn’t powerful enough to handle it.
Furthermore, the official TDP values from Intel and AMD for their CPUs are not even close to the actual power consumption figures because they refer to normal hours and do not boost hours. With the increased frequencies, CPUs are drawing much more Watts than the official TDP of the PSU, and things get worse, of course, if you decide to overclock.
Even at default settings, some high-end CPUs can demand power of 300 watts or more. Yes, we’re looking at you Mr. Core i9 11900K. If you combine this with a high-end GPU power consumption, you’ll quickly find that you need an 850W or even more powerful PSU for a high-end gaming system.
The dimensions of the PSU play a role in building your next system. You cannot use a standard ATX12V power supply in a mini-ITX chassis that requires an SFX PSU, for example. Fortunately, desktop PSU form factors are limited to the following
- ATX12V (PS/2) [reference dimensions: 150mm (W) x 86mm (H) x 140mm (D)]
- SFX12V 80mm fan [reference dimensions: 100mm (W) x 63.5mm (H) x 125mm (D)]
- SFX12V 80mm Low Depth Fan [reference dimensions: 125mm (W) x 63.5mm (H) x 100mm (D)]
- SFX-L [reference dimensions: 125mm (W) x 63.5mm (H) x 130mm (D)]
SFX-L is not an official ATX specification format, as it was introduced by Silverstone in 2014 and later adopted by many other brands. It has a longer depth of sound effects to allow for a stronger platform.
You may have heard of the ratings for titanium, platinum, gold, and other metals in PSUs. These refer to the efficiency of the PSU, in other words, how much power the PSU draws from the socket to deliver power to your system. The more efficient the energy source, the better for the environment because it reduces carbon emissions. Moreover, you can also save money on electricity in the long run.
Currently, both competency accreditation agencies use roughly the same ratings, which you’ll find below:
- Diamonds (Cybenetics)
- White (80 PLUS)
Another important decision that you have to make before you invest in a new PSU is the type of cable to choose; Standard or not? High-end power supplies, which cost more, usually come with fully modular cables. You’ll generally find stationary cables only in the budget categories, and somewhere in between, you’ll find semi-modular PSUs. Many of them also belong to the budget or middle class categories.
If you can handle fixed cables and need a PSU for a main system, there is no need to pay extra for a fully modular unit. But if you’re aiming to use minimal bare cable, without a ton of wires floating around your system, a full or semi-modular setup is the way to go.
More and more people are starting to realize the effect of the PSU on the overall noise output of the system. As strange as it may sound, your power supply can play a significant role in your computer’s noise under load.
The higher the efficiency, the lower the heat load, so the PSU fan will not have to spin at high speeds. This means that your best bet for a silent PSU is to purchase one with the highest efficiency rating possible. However, this does not mean that you will select a quiet power supply, so it is a good idea to read some reviews before continuing with your purchase.
We’ve noted our tested noise ratings in our best power supply guide to give you an idea of how the best PSUs sound. Cybenetics offers PSU noise certifications, so with a quick look at the corresponding database, you’ll find the PSU that meets your audio requirements.
Cybenetics noise ratings are listed below:
- A++ (<15 dB)
- A+ (15 to 20 dB)
- A (20 to 25 dB)
- (25 to 30 dB)
- Standard++ (30 to 35 dB)
- Standard + (35 to 40 dB)
- Standard (40 to 45 dB)
That’s all you really need to know about choosing the right power supply as a PC gamer, but if you really want to research how a PSU works, we’ve got some words for you. These are the deep electrical stuff, but wattage, efficiency, cables, and noise levels are the most important things to think about when you’re actually looking to buy a new power source for yourself.