How to choose a power supply for PC

The power supply is not so attractive for users as a new processor or of the video card, but it is a very important component of a PC, which certainly should not be attempting Save. We collected a detailed guide, in which we will tell you what you need to know when buying.

Power supply (BP) - the heart of the components of your PC, and when buying a low-quality device there is a big risk that the entire computer can fail!

Let's see what you need to know that the power supply is proper when the PC is assembling.


Power is a basic indicator that will help determine which power supply you need. Simply put, it shows the total amount of watts that the power supply can transmit various PC components. It is worth indicating that all devices are different: some models are given up to 300 W, while others - up to 1200 watts.

The box of each power supply indicates the power indicator, however there is a hidden factor. Which? Take, for example, the power supply is a power of 500 W. In the technical characteristics of the device, it will be indicated either "constant power" (which is fine), or "peak power" (that is, the maximum).

Permanent and peak power are nominal values ​​based on the manufacturer tests. Power constant means that the power supply can provide these 500 W continuously and constantly. The peak power indicates the maximum indicator, that is, the power supply will be able to give 500 W only for a while, and then the indicator will again decrease.

So we recommend always buying power supplies only with a constant power, not peak.

How many watts?

Naturally, all computers are different, so the amount of energy varies depending on the device. So, a high-performance game PC for uninterrupted work will be required more watts than a simple home office computer. This is due to the fact that for operation of powerful processors and , video cards requires much more energy.

If you buy an inappropriate power supply, then the PC simply will not have enough power during intensive processes. However, how to accurately find out the right amount of watt? Fortunately, on the Internet there are full resources that will help calculate the power consumption of the computer.

We recommend two tools: Power calculator from Bequite (Available in Russian) and from Cooler Master.

Both instruments will give an idea of ​​which power is necessary. Also, do not hesitate to round the resulting values ​​into the biggest.

In fact, you can even climb two steps above. For example, if the calculator says that you need 370 W, the power supply is perfect for 400 W, as well as 500. It is also worth considering the possibility of updating parts in the future.


Purchase of an energy-efficient and certified power supply will help save big money.

What is it? The power supply of this type converts alternating current into a constant with minimal loss of electricity. After that, all power is distributed to PC components.

Usually, BP spends part of the energy to the conversion process. Consequently, the efficiency of the device depends on how much energy it can convert, and how fast.

Thus, 80% of the efficiency means that the power supply may convert 80% of the AC power to constant. Similarly, 50% efficiency means that the power supply converts 50% of the AC power to the permanent. Simply put: the higher the percentage of efficiency, the better.

The most effective power supplies have an 80 Plus rating. This rating is assigned to an independent certification authority. However, even power supplies 80 Plus have different levels: 80 Plus, 80 Plus Bronze, 80 Plus Silver, 80 Plus Gold, 80 Plus Platinum, 80 Plus Titanium.

An additional advantage of energy-efficient power supplies is that they allocate much less heat than standard devices, and create less noise when working.

Other parameters

All previous items covered the main aspects of the choice of power supplies. As in the case of any other component, you can only get better information in some details. If you are a novice, then the aforementioned three criteria are more than enough when making a purchase decision.

If you understand the PC in the "stuffing", then in the process of choosing the power supply, come across many other terms. Some of them have a lot of importance for ordinary users, while others are very important. We will talk about them just below:

  • AT - ATX - MATX: It is quite often possible to meet the power supplies developed for computers with AT, ATX or MATX. These terms are used to describe motherboards of different sizes and structures and, therefore, have different nutritional needs. That is why it is necessary to check how the motherboard is installed in the PC, and buy the appropriate power supply to it.
  • Channels: There are "single-channel" and "multichannel" power supplies. Both have their pros and cons, but it is not necessary to worry about technical details. If you live in an area where oscillation or power outage is a normal phenomenon, you should consider using multichannel BP. In any other case, or when using a good uninterruptible power source, purchase a single-channel power supply.
  • Stability of the voltage : If you take into account all of the above items, the stability of the voltage should not be a problem. Stability is, in fact, the ability of the power supply to maintain a 12 volt nutrition without interruptions.
  • Cables or connectors : If you are not going to buy a high-end power supply, then you should not think about cables. High-quality power supplies offer the so-called "modular panel", into which you can connect only what is needed (i.e., the cable can be disgusted, which will help bring order and improve PC ventilation).
  • Repair and accessories: There are no instructions for repairing the power supply. If you find a problem, your only option is to purchase a new device, or hope that it is still under warranty.

should not save

Why do we talk about Buying a quality power supply instead of just use the one that comes with a PC case, or purchase a model relative to an unknown brand?

As we said above, the power supply affects each component of the PC and can lead to a failure of the entire system in case of power fluctuations. However, in addition to this, high-quality power supplies have other advantages:

  • Durability - If you now buy a high-quality power supply with a capacity of more than 200 W, that is The high probability that you can use it upon subsequent updating of PC components.
  • Resale - decided to buy a new power supply? You will surely find buyers for your old on the secondary market!


Various companies constantly produce new models of power supplies, and taking into account the low popularity of this component, not all Know about large players in the market. Here are some well-known and respected brands: Corsair, Cooler Master, Antec, Be Quiet, Seasonic and XFX.

After performing all the aforementioned steps, you must have a clear idea of ​​which voltage indicator should be in BP, which models have 80 Plus certification and much more.

An important factor when choosing a power supply - real customer reviews that can be found on various sites on the Internet. One of the main is Yandex. Market, where each product has an average rating and customer reviews.


Power supply - Important and complex in terms of selecting a PC component, but if you know about all the basics that we described above, choose The power supply for the game computer will not be difficult!