How to Choose a PSU


Power supply (or PSU , Power Supply Unit ) is the component of the computer that is responsible for adequately distributing the electrical current to all the remaining hardware installed, based on the type of the latter: for example, the amount of electricity required by the CPU is completely different from that required by a DVD player, a SATA device (hard drive or SSD) or a powerful video card.

You can compare the PC power supply to an energy conductor : it knows exactly how much electricity to supply to each component, at any time and in any situation, so as not to cause any kind of damage, thus avoiding running into even dangerous scenarios.

You can choose CPU in this article : Top 5 Best Motherboard CPU Combination

The other tasks of the power supply include the stabilization of the electric current received from the home socket (which could in many cases be variable voltage, especially if you live in an area with a high risk of lightning), the emergency stop of the electrical supply in the event of a short circuit , overload or overheating , as well as the possibility of using a physical switch to be able to immediately interrupt the power supply (this button, usually, is always located close to the input plug and is identified by the I / O or ON / OFF).

Choose a PSU

How do I choose the right power supply?

  • The first parameter to consider when choosing a PSU is certainly the capacity or power , that is the maximum load that the power supply can support to correctly power all the various components.

The capacity is indicated in Watts (the unit of measurement of power) both on the packaging and on the label of the power supply: for example, by choosing a 500W power supply, the computer has a maximum power of 500W available in ideal conditions (I will return on this aspect shortly).

It must be said, however, that each component has a different electrical consumption and that, in order to understand whether or not the capacity of a certain power supply is sufficient to withstand the required load, the overall consumption of all components must be considered. Performing this calculation manually could be quite complex, especially for those who do not have at least a general smattering of electronics: it is for this reason that, to simplify the choice, it is possible to use specialized sites that automatically perform this operation.

  • Another parameter to be taken into consideration in order to choose the correct PC power supply is the modularity of the cables to be used to connect it to the various peripherals.

non-modular power supplies , for example, the cables are already installed in the “box” and protrude from a corner of the same: in this way, you can be sure of having all the possible connectors available, however it may be inconvenient to find a place , inside the case, to those that will not be connected to any device.

Other types of power supplies, on the other hand, have a certain number of pre-installed cables (usually those dedicated to the motherboard and CPU) and are equipped with some ports to which you can connect, if necessary, the additional necessary cables: in jargon, this type of PSU is defined as semi-modular .

  • The last parameter to consider when choosing a power supply, but only in order of list, corresponds to the dimensions of the same: as far as possible, they are standardized on the basis of form factors compatible with the various cases available in trade .

Before purchasing a new power supply, it is therefore essential to have in mind the type of case in which it must be installed, so as to know the supported form factor and the maximum dimensions that can be used in terms of depth (some high-end power supplies, typical of computers gaming, they tend to be deeper than normal)

How many watts PSU do I need for my PC?

When shopping for a new custom or gaming PC, the power supply is usually one of the most neglected components, but also one of the most important. The power supply is the component that supplies energy to all the other parts of the computer, consisting of a fan, a transformer, the external socket for the electrical cable that goes to the wall with a switch and then a whole series of cables and internal connections that must be connected to the motherboard and disks.

Morealso, choosing which power supply that is ideal for a computer does not mean taking the most powerful (the one with the most Watts) of all, but the most proportionate one according to the internal hardware. Having one that is too small, in fact, could not guarantee sufficient energy needs and cause problems when turning on the computer and its operation, while one that is too powerful could consume more energy than it should with a net waste that can be felt on the bill, as well as damage internal hardware components.

First of all it is important to point out that non-certified generic power supplies are very inefficient and waste a lot of electricity, even when you are not actively using your PC. For example, if your computer requires 100 watts to run and inside, the budget power supply will draw 150 watts from the electrical outlet. The certification for PC power supplies is called 80+ , which indicates greater energy efficiency and less energy waste. With this certification, depending on the level of efficiency obtained, there are different energy saving classes:

How to assemble a gaming power supply

To assemble a good gaming computer , hardware components that are very expensive in terms of power consumption are required: for this reason, you don’t have to spare any expense with regards to the PSU, aiming straight at a high-end device. A good example is the  Corsair TX650M , a semi-modular ATX PS / 2, with a maximum power of 650 W (but also available at higher wattages) and 80 Plus Gold certification.


Leave a Comment