How to choose the right power supply for your computer

How to choose the right power supply for your computer

Power supply is one of the most important components in the computer and of course, the only one, that any other component can’t work without. The quality of power supply is very important for the normal operation of you computer but it’s not responsible about how fast it would be. Therefore, if you replace it with new one, perhaps you won’t feel that you’ve made an upgrade (except that perhaps the new one would be more silent). Very often its importance is overlooked by many users who prefer to invest the money saved from a power supply in more memory, or faster processor.
Typically, a power supply is selected depending on the required power of individual power lines. As you probably know, the main load falls on the 12V line, so exactly the power provided by this line is very important. Many users make mistake taking the maximum values of current provided by any individual power line and multiply them by the voltage to obtain the output power. That is wrong because the 3.3V and 5V as well as different 12V lines are dependent on one another and that’s why in the specifications for +3.3 V, 5V and +12 V is given their combined power.
To determine what power you need you have to calculate the consumption of your computer components. There are many online calculators, which you can use for this purpose, but you should know that there is no such situation in which all components are loaded to their maximum values. For example if you have two hard drives and one optical drive in the worst case you will have two active working devices. Also in 3D games and applications the mainly loaded device will be the video card, unlike the CPU which will be away from its maximum load. It is also possible the opposite situation, where the processor performs havy calculations, while the video card stays almost unused. Typically, the actual values are about 75-80% of those made by such calculators, but if you add additional capacity for future upgrades, the values calculated in such a way would be quite normal. For a modern computer, as a minimum can be considered values of approximately 350W.
The next thing that you should pay attention to, when purchasing a new power supply is the energy efficiency. The higher values mean that your power supply will convert the voltage from the electrical network more effectively and of course it will produce less heat and noise. Most widely used power supplies have an energy efficiency ratio of about 70-75% but higher-quality power supplies can be over 80% efficient.
Most power supplies are equipped with 80mm or 120mm cooling fans. Larger fans recommended because of the small amount of noise they produce compared with the 80mm fans. There are also the so-called “completely silent” models without fans. They have specially designed cooling system with high efficiency, but are usually considerably more expensive and their power is limited to about 300W – 500W.
Another important requirement for the power supply is to have a sufficient number of connectors, which can save you a lot of problems when adding new hardware. There are also Modular Power Supply Units in which the users can modify the power connectors to suit their personal needs. Unlike the conventional design where power cables are permanently connected to the power supply, a modular power supply provides an option allowing unused cables to be detached from it. By allowing cables to be detached, modular cabling can help you not only to reduce the clutter of unused cables but also improve the airflow within the case.