If you want to upgrade your computer, components such as hard disk, memory or graphics card immediately come to mind. Choosing the right PC power supply is less prominent, but just as important, because the correct power supply for your computer stands or falls with it. This guide will help you to figure out what specs to look out for before buying, so you can make the right choice.
What power does my power supply need?
The power of a power supply is crucial for the proper performance of your PC. Basically, it can be said that power supplies only draw as much current from the line as they need for operation. A capacity that is too high will fizzle out. And one that is too low will have an impact on performance. It is important to consider the purpose for which you are using the computer: An office computer per se already has lower requirements than a high-quality gaming PC. Accordingly, there are corresponding power supplies for each type of use of the computer.To find out how high the power consumption of your computer system is, you can either learn from the manufacturer’s specifications or use one of now numerous watt calculators to determine the performance. Since a power supply works best at a load of 45 to 75 percent, you should not forget to plan an additional buffer if you want to install additional hardware components. The following list is intended to provide a rough overview of the required power specifications:
- An office PC that does not use a lot of multimedia needs about 200 to 300 watts
- Gaming PCs with cheap or mediocre graphics cards are between 400 and 500 watts
- The more powerful the components, the higher the performance of the power supply unit should be. Accordingly, high-quality gaming PCs require at least a 600 watt power supply unit
- Overclockers work with up to 1,000 watts
Performance equals performance? That means 80 Plus
A computer needs a voltage of 12 V to run. Strictly speaking, the current from a car’s cigarette lighter would be sufficient for operation. However, commercially available electricity from the wall socket has a voltage of 230 V – almost twenty times the requirement of a PC. The transformation from 230 to 12 volts generates heat that is not included in the performance. So you are paying for electricity that you are not using.So that end consumers know at what efficiency their power supply – and thus their computer – is working, the six-level 80 Plus certificate was introduced. The basic level guarantees you an efficiency of 85%, the rest is lost during the conversion to 12 V. In five further stages up to Titanium, the efficiency increases up to 96%:
- 80 Plus: 85 % efficiency
- 80 Plus Bronze: 88 % efficiency
- 80 Plus Silver: 90 % efficiency
- 80 Plus Gold: 92 % efficiency
- 80 Plus Platinum: 94 % efficiency
- 80 Plus Titanium: 96 % efficiency
If you have a gaming PC with an output of 500 watts, a simple 80-Plus power supply unit draw almost 90 watts more power to ensure performance. An 80 Plus Gold power supply only needs about 545 watts for this, and an 80 Plus Platinum power supply already manages the 500 watts of power with about 520 watts. If you let your computer run for around eight hours a day, you can save around €55 per year at a hypothetical price of 30 cents/kWh if you use a high-quality power supply.
However, keep in mind that the highest standard will, of course, cost the most. Therefore, try to calculate which standard is the best for your requirements. If a possible purchase would not have paid for itself within two years, go for a device that is at least one level lower.
Cooling and volume of power supplies: What should be considered?
Similar to other components, it is also essential that power supplies do not overheat during operation. The specified performance and the expected service life can only be guaranteed at the appropriate operating temperature. Therefore, when buying, make sure that the cooling of your new power supply is up to the demands that your use will cause.A basic distinction is made between bearing and (partially) passive cooling when cooling a power supply. The Bearing variant can be divided into Sleeve, Ball and Fluid Dynamic Bearing. While sleeve bearings use oils and greases to keep noise emissions low, ball bearings use rolling bearings made of balls. Fluid Dynamic Bearing, on the other hand, relies on full lubrication in the form of oils or gas to achieve virtually frictionless rotation.
The important thing with these active cooling systems is that you must be able to independently adjust the rotor so that it is only audible when the load is 80%.
Passively operated cooling systems, on the other hand, are designed in such a way that even the high-quality subcomponents prevent overheating. The BQT BN331, for example, uses the be quiet! patented stay-up ventilation system and thus achieves a performance level of 80 Plus Titanium.
The perfect power supply for your needs
Try to give enough thought to your requirements before purchasing a power supply unit. How much power does your power supply need to deliver? 300 watts or rather 600 watts? What level of efficiency is amortized within two years if purchased? Which cooling variant meets your requirements? If you want to give your computer an individual touch, use a power supply with RGB lighting. Also note that you will likely replace your power supply less often than other components in your PC. If you have an answer to all of these questions that suits your requirements, then nothing stands in the way of choosing the right power supply unit. A large selection of power supplies can be found in the reichelt online shop.
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