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How To Choose A Power Supply ?

One of the most difficult components for first-time builders to choose is their power supply. Power supplies won’t improve your framerate and they aren’t really a big part of your system’s aesthetics. However, there is no component more central to your system’s long-term health than your power supply.

If you choose a low-quality power supply, your build will either not run, or it will suffer over the long term. On the other hand, if you don’t understand how much power you need in order to efficiently power your system, you could end up allocating more of your budget towards your power supply than is necessary and, as a result, lose out on actual system performance.

Important key point before buying a PSU (Power Supply Unit):

  • Form Factor

  • Wattage of PSU

  • Power Efficiency

  • Modularity and cables

  • Premium Power Supply

Form Factor

The next consideration is a simple one – you’ll need to pick a form factor that you’re sure will physically fit into your case. Fortunately, there are standards in terms of power supplies just as there are in cases and motherboards.

This topic can get quite complicated, but the important thing to remember is you’ll want to match your power supply with your case and motherboard. The following is a basic overview of the most important power supply form factors today.

  • ATX

  • ATX12v

  • EPS12V, SFX12V, and Others

One consideration when it comes to PSU form factor is the physical size of the unit. For the vast majority of desktop PC users, standard ATX power supplies should be fine. If you’re a small form factor PC (SFF) enthusiast, you’ll want to do a little more research to make sure your PSU will fit. There is a wide variety of SFF PSU sizes, like SFX, CFX, and more, so make sure you find the PSU that works with your case, no matter how small your PC.

Wattage of PSU

When selecting a new PSU, one of the most common questions asked is, “How many watts is enough?” As is often the case in the world of PC hardware, the answer varies widely depending on the unique needs of your system.

Generally, more complex systems require more power to run. A desktop with a custom liquid cooling loop, a high-end motherboard, and dual GPUs is going to need a higher wattage computer power supply than a simpler system.

It’s impossible to give an exact recommendation without knowing specifically what hardware you’re working with, but using a PSU Wattage Calculator, or determining the power draw of your different internal components and adding that together, can give insight into how many watts you need and Always make sure the PSU you purchase has sufficiently high continuous power output, and don’t choose solely by peak power capabilities.

Power Efficiency

Wattage is certainly an important consideration when choosing a desktop power supply, but so is PSU efficiency. Inefficient delivery leads to wasted power and more heat, which can potentially decrease the lifespan of your components.

Because this is such an important consideration, there’s a relatively straightforward independent rating system in place. You might have noticed the “80 Plus” rating on many power supplies, often listed alongside a precious metal. To receive this rating, a power supply must be at least 80 percent efficient, meaning that a maximum of 20 percent of power is lost as heat.

The more efficient your PSU, the less power it uses, and the less heat it generates. That said, higher efficiency usually means a higher price, so you’ll want to find the balance that works for you. Even the most efficient PSU will still generate heat, however, and most use fans to disperse that heat. Many power supplies are designed so that the fan will only turn on when it needs to — that is, when the PSU hits a certain threshold. Features like this help to reduce noise.