In turn, the thermal power that is released when the power supply element is heated will directly depend on the strength of the current that passes through all consumers.

It should be remembered that the sum of all the powers consumed by the components should not exceed the output power of the power supply.

How to correctly calculate the power of a computer?

When calculating the power of a PC, it is important to consider that the system consumes power unevenly. The maximum takes the moment of turning on the computer or a separate device, reading / writing disks, transferring information from / to HDD, simultaneous launch of many programs, etc. For devices that, due to their specificity, consume a large amount of energy, manufacturers often indicate the peak power value. It follows that the maximum that the system as a whole will consume can be calculated by simply adding the power of all devices that are connected to the power supply.

Next, we will offer you an approximate diagram of power consumption by various computer components:

• the central processor consumes an average of 50 to 120 watts. Moreover, the higher the clock frequency, the greater the power consumed by it.
• the motherboard consumes an average of 15 to 30 watts. Moreover, if the board has integrated devices, for example, a sound card, then, accordingly, such a board requires more power.
• power consumption of the graphics editor - from 60 to 130 watts. And if the video card has additional power, it consumes more than those that do not have it. Accordingly: 50-70 W - without additional power and 100-130 with it. At moments of maximum load (for example, during resource-intensive games), the power consumption of modern video cards can increase up to 300-400 watts.
• modules random access memory consume from 5 to 20 watts. Consumption directly depends on the capacity of the module. In addition, if there are various "hitches" on the memory module, such as filter capacitors, power consumption increases.
• hard drives consume between 15 and 60 watts. Moreover, when the hard drive is actively working (files are being searched, information is being copied or written), power consumption is reduced to a maximum. It also occurs when the computer is turned on, when the hard drive is being diagnosed, which is necessary to identify critical errors.
• 10 to 25 watts are consumed by CD/DVD drives. The value itself depends on the maximum rotation speed of the disks, as well as on the actual mode of operation. Moreover, if the disc is scratched or simply poorly recorded, much more power is consumed, since the drive constantly has to change the rotation speed. The record holders in terms of power consumption are the so-called Combo drives, which combine the capabilities of reading CD and DVD and writing CD-RW.
• Floppy drives consume 5 to 7 watts. In this case, the power consumption depends mainly on the manufacturer. Since the speed of their work remains the same in any modes.
• sound card consumes 5-10 watts. Here, the higher the class of the sound device, the higher the power consumption. So, Hi-Fi devices require an order of magnitude more power than middle-class sound cards.
• cooling system fans consume an average of 1-2 watts. However, it should be remembered that the fans themselves in a computer can be five, or six, or even more: on the processor, video card, hard drive, in the power supply itself, etc.
• input / output ports consume 8-10 watts. AT modern computer there are usually six such ports: one COM port, 4 USB and one LPT. In addition, a line-in/out is added to the sound card, plus a microphone-in.
• network cards consume an average of 3-5 watts.

Here are some more factors that should be taken into account when we consider such a question as computer power. Having calculated the approximate power figures, before buying a power supply, you should consider that you need to leave some margin due to the upcoming system upgrade opportunities and the installation of additional devices.

Let's remember a simple truth - so that the power supply does not fail and does not burn out, you should not overload it. In addition, cleanliness should be monitored, as simple dust can contribute to the critical overheating of the power supply and its failure.

Some power supply manufacturers provide these “Online power supply calculators”, where you can make a fairly accurate calculation.

Thus, summing up the information presented above, having become acquainted with the principle of operation of the power supply, as well as with the power consumption indicators of all the main computer devices, we hope that now the question “how to calculate the power of the computer” and choose the optimal power supply for it will not seem to you solvable. After all, for this you just need to make simple mathematical calculations.

If you still have questions about how to calculate the power of a computer and choose a suitable power supply, then you can always contact the computer help center site, our engineers will advise you on all your questions. In addition, you can order the installation of a new power supply in your system unit from us.

When buying a computer in a ready-made configuration in a store, many simply do not pay attention to which power supply is installed in the purchased case. And absolutely in vain. After all, the stability and durability of your computer depends on the power supply unit (PSU). Due to a poor-quality or low-power power supply, the computer may spontaneously turn off, give an error, or simply freeze.

Ultimately, this can lead to premature failure of expensive computer components. Therefore, it is recommended to always be interested in which power supply is installed in the system unit. And it is best to choose a power supply yourself and purchase it separately from the case. What are the important aspects to pay attention to when choosing a power supply?

Power supply power

The main parameter of any power supply for a computer is its power. This parameter must be calculated individually for each PC, depending on the power consumption of all system components. The correct calculation of the PSU power is one of the guarantees optimal choice power supply for your computer. Naturally, in order to calculate how much energy your computer consumes, you need to add up the energy consumption parameters of all its individual nodes - processor, video card, etc.

To do this, you can go to the websites of manufacturers of devices installed in your system unit and find out the power consumption of each system component. After adding up the power consumption of all devices, add about 15 to 25 percent more to the resulting value. This reserve is needed so that the power supply does not work all the time at its maximum power. Thus, the resource of its use will increase.

For automatic power calculation, you only need to select the components of your system unit, including the type of processor, motherboard, RAM, video card, hard drive, additional devices and specify the number of installed components. It is worth noting that not all of these online calculators consider the same and sometimes the difference between the optimal power values ​​​​in two different calculators can exceed 100 watts.

When choosing a power supply for your PC, pay attention not to its peak power, but to its rated power, that is, to the power that the power supply can reliably provide continuously for a long time. You also need to keep in mind that each of the devices in the system unit is connected to one or more voltage channels, consuming current from them. The power supply produces different voltages on several of these lines. The main load falls on the channels + 12V. It is to these channels that the processor, video card, hard drive and other fundamental components of the computer are connected. Therefore, it is best if there are several such channels in the power supply (+ 12V1, + 12V2, + 12V3, + 12V4, etc.), and their total power will be as large as possible.

Today, almost any home or office system will require a 400-500 W power supply. In general, even for a mediocre or already slightly outdated computer, it is advisable to purchase a medium or powerful power supply. For home and gaming systems, power supplies with a capacity of 450 - 550 watts are suitable. For more advanced gaming systems or computers with two video cards, it is recommended to purchase power supplies with a capacity of 600 - 700 watts. If you are planning to overclock your system unit components, then it is also better to prefer a more powerful power supply.

Types of power supplies for a computer

According to the type of connection of outgoing lines, all power supplies can be divided into three types:

Standard

The standard power supply is a cheap and simple model in which all cables are directly connected to the PSU. This ensures less losses during wired transmission. But in the system unit, there is a mess in the cables, which creates certain obstacles to the free circulation of air and the efficient operation of the cooling system.

Modular

In a modular power supply, cables are connected to it through special connectors, so that the user can connect cables as needed. Using a modular power supply allows you to get rid of unused cables, organize them and, thereby, ensure free air circulation inside the system unit. The disadvantage of modular PSUs is high losses during wired transmission.

hybrid

Such power supplies combine the advantages of standard and modular power supplies. In them, the most important cables are connected directly to the power supply, and additional cables are connected via a modular solution. Thus, both ordering of cables inside the system unit and lower losses during wired transmission are achieved.

Power Factor Correction (PFC)

It is important that the power supply you choose has a so-called power factor correction or PFC (Power Factor Correction) module. The presence of capacitors and coils in the pulse power supply circuit leads to the fact that the network energy is converted into consumed energy non-linearly.

Power factor correction (PFC) is designed to smooth out the resulting ripple and "stretch" it over time. Thus, the power factor is corrected and the operating parameters of the entire power supply circuit are stabilized. The PFC module in the power supply can be passive or active:

Passive PFC

The passive PFC model is a conventional coil (choke) that smooths out voltage ripple. However, the efficiency of the passive module is very low, so it is installed only in inexpensive, budget PSUs.

Active PFC

The active power correction system is an additional board that stabilizes the input voltage and "swallows" short-term voltage dips. The active PFC model provides an almost perfect power factor, filters out mains noise, and generally improves the performance of the power supply. Of course, it is recommended to purchase a PSU with an active power correction system.

Other power supply parameters

The power supply should ideally be as quiet as possible. Fans on the power supply are usually installed both on the side wall and below. Cheap power supplies often do not provide for an automatic fan speed control system. This leads to the fact that the fan in the PSU runs at maximum speed, creating increased noise and often simply overheating. When choosing a power supply, you need to pay attention to the fan or cooler. It is desirable that it be as large as possible, for example, 120x120 mm in size. The larger the cooler, the less noise from its operation.

It is also widely believed that in order to determine the quality of the performance of the power supply, it is necessary to support it in your hands and evaluate its weight. The large weight of the power supply indicates the lack of savings on components, the large size of transformers with radiators and the optimal number of chokes.

However, this point of view already looks outdated, because modern models of power supplies for PCs can have relatively low weight and dimensions with phenomenal power. This is achieved by reducing the size of the power transformer and an improved power supply circuit.

But on the manufacturer of the power supply, of course, you need to pay close attention. Power supplies from trusted and well-known manufacturers, of course, can also be defective, but still their products are not manufactured in artisanal conditions and undergo certain quality control. Among the power supplies from unknown manufacturers, unfortunately, there are many products with disgusting build quality and inconsistency with the declared characteristics. Among the reliable manufacturers are power supplies from FSP, Cooler Master, Antec, OCZ, Zalman, Enermax, Hiper and some others.

Of course, you should not once again save on buying a power supply for your computer. After all, such savings can turn into a need for you to purchase a new motherboard or processor that has failed due to failures in the PSU. Remember that buying a branded and high-quality power supply of the required power is one of the guarantees for the stable operation of your PC.

80 years have passed since then and I still ask myself the same question ( approx. - What is electricity?), but unable to answer it. © Nikola Tesla

Power Supply Power Calculators

If you came here only to calculate the power for your PSU, then

The importance of the power supply

Component quality

The quality of the installed electronic components has a significant impact on the final price. An example here is the electrolytic capacitors used. The power supply is a node that heats up significantly during operation, especially if the PC has a ventilation scheme that creates a vacuum inside the case, in which part of the hot air moves through the PSU. The most common and inexpensive aluminum electrolytes have a maximum allowable temperature of 85 °C, but even slightly lower heating significantly reduces their MTBF. In reliable power supplies, conscientious manufacturers use more resistant types of capacitors, but the price of the product is higher. The choice of the manufacturer in favor of specialized diode assemblies or discrete elements has a corresponding effect on the final cost. In the first case, the bridge rectifier is guaranteed the identical performance of both arms and the maximum possible symmetry, and in the second case, a higher profitability of production.

circuit solutions

Modern power supplies can have several independent lines in +5 and +12 V circuits. The ideal, albeit expensive, circuit solution here is separate rectifiers (especially synchronous), and individual output filters are acceptable. In budget models, the most primitive options for obtaining “parallel” lines are often found, implemented by simply connecting wires to a common contact. The obvious disadvantage of such a simplification is the impossibility of effectively stabilizing the output voltage and the mutual influence of consumers. Cheap PSUs may not have EMI input filters or are equipped with simplified single-loop solutions. In other words - with a high probability they will create problems for other electrical appliances in the course of their work.
If budget power supplies usually provide two types of protection: against short-term overvoltage in the external network and short circuit inside the unit, then high-quality devices support a more advanced security package. The best models are equipped with an intelligent circuit based on a special chip and are able to respond in a timely manner to excessive current consumption, overheating and undervoltage. In addition, inexpensive blocks do not have protection that prevents them from being turned on without a regular load, while such an operating mode is not terrible for expensive solutions.

Consequences of the choice

Spontaneous reboot of the computer can be caused not only by the unstable operation of the motherboard, memory problems or software reasons. Any power supply controls the output voltage level in all circuits and generates a control signal that allows the PC to be turned on. The latter is a logical unit that enters the input of the corresponding key element of the motherboard responsible for issuing the general reset command. The absence or short-term loss of the Power_OK signal automatically causes a reboot of the system, and the cause can be either the voltage going beyond the permissible limits or the incorrect operation of the control unit itself. For low-quality PSUs, the opposite manifestations are also possible, for example, the low speed of operation of this protection, tracking not all circuits, or giving a signal until the levels are completely stabilized (insufficient delay).
Another characteristic feature of budget power supplies is the use of the minimum allowable values ​​of electrolytic capacitors installed in the output filters. Their capacity directly affects the shutdown time during which the PSU is able to maintain the required voltage levels, allowing the computer to urgently complete critical operations. In the event of a short-term loss of mains power, it is even possible to continue the operation of the PC without rebooting. Simply put, some high-quality PSU models have a “built-in uninterruptible power supply”.

One of the most important components of a computer. It provides power to all other components and the stability of the entire computer depends on it. Therefore, it is very important to choose the right power supply for your computer. In this article we will talk about how to choose a power supply for a computer.

The power of the power supply.

The first thing you need to decide is how much power you need. depends on the components that are installed on the computer. The easiest way to find out the required power supply capacity is to use a special calculator. The most popular calculators are:

Using these calculators is very easy. All you need to do is fill out a form in which you need to select the components that are installed on your computer from the drop-down lists. After that, the calculator will show the maximum sum of the peak powers of all the components you have selected. You can already focus on this figure when choosing a power supply.

But, you should not pick up a power supply, the power of which is enough back to back. It should be borne in mind that the actual power of the power supply may be lower than what the manufacturer claims. In addition, keep in mind that the configuration may change over time. Therefore, it is better to take a power supply with a small margin. For example, you can add 25% to the power that the power calculator will show.

Power supply cooling system.

Another important point when choosing a power supply is the cooling system. Pay attention to the number of fans and their diameter. Most modern power supplies are equipped with just one fan with a diameter of 120, 135 or 140 millimeters. It must be borne in mind that the larger the fan, the more. Therefore, it is best to choose a model with the largest possible fan.

Also on sale there are models with one or two fans 80 mm in size. As a rule, these are very cheap models. Such power supplies make a very loud noise, so you should not buy such models.

Another option for a cooling system is passively cooled power supplies. Such power supplies do not make any noise at all, since they are not equipped with fans. But, in the case of buying such a power supply, you need to take care of additional cooling for the system unit.

Cables and connectors.

Also, when choosing a power supply, you need to pay attention to the cables and connectors with which it is equipped. Power supplies are available with fixed or pluggable cables.

In the first case, the cables are rigidly fixed in the power supply. In this case, all unused cables will hang aimlessly inside the system unit, blocking the air flow and worsening its cooling. If the power supply allows you to connect and disconnect cables, then the user can connect only those cables that he really needs. This approach reduces the number of cables inside the system unit and improves its cooling. Therefore, when choosing a power supply, it is best to choose a model with plug-in cables.

Power supply price.

Price is also an important point when choosing a power supply for a computer. You should not save too much on the power supply, buying the cheapest model that fits the power. As a rule, such models produce much less power than their manufacturer claims.

It is best to choose a power supply from a well-known manufacturer that has long established itself in the market. Now such manufacturers are FSP, Enermax, Hipro, HEC, Seasonic, Delta, Silverstone, PC Power & Cooling, Antec, Zalman, Chiftec, Gigabyte, Corsair, Thermaltake, OCZ, Cooler Master.