PC Power Supply Units (61 products)

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Power Supplies for your system

If your power supply does not provide enough power for your system, it can cause serious performance issues or system errors. Whether you are building your own PC, or need to replace a faulty power supply, it is important to work out the type and wattage of the power supply you need. It is important to check the efficiency rating of your power supply; 80%+ efficiency PSUs are a better option, as they waste less electricity, and do not create as much heat inside your system. You should also consider whether you are looking for a modular or non-modular power supply this will impact the way you build your system, manage cables, and upgrade in the future.

How do I know which power supply I need for a computer?

Which power supply you should buy depends on the components in your computer, and what you use the system for. Generally speaking, you should aim for a power supply that delivers a wattage at least 40% greater than the wattage used by your hardware combined. You will also need to consider the processes you use your computer for your system will work harder when running more demanding programs or games, and therefore will require more power. As a result, gamers and designers will need more headroom than those who use their computers for social media or admin tasks.

What is the power supply on a computer?

The power supply unit (PSU) in your computer converts alternating current (AC) from your plug socket into a continuous current (DC) to run the hardware in your computer. It is essentially the system that provides electricity to your set up, allowing it to power on. A low quality or under-powered PSU will cause erratic performance, and potentially damage your system.

What voltage is a PC power supply?

The power supply itself does not have voltage, it converts voltage from the plug socket into a low voltage direct current (DC). In Europe, this is usually around 220-240 volts, and the DC it is converted to will vary.

What parts are powered by the computer PSU?

The motherboard, CPU, RAM disc drives, hard drive and more or less everything contained in the computer chassis are powered by the power supply. All the external devices such as printers and monitors have a standard power source such as the mains power supply. If you have a laptop or an All-in-one computer, the display is powered by the computer power supply.

Does the fan use a power supply?

Whenever your computer is on then the fan should always be running. If the fan is not moving, and by moving we mean spinning, then your computer needs attention. Either the fan itself is broken or the power supply needs looking at. There are certain power supplies which have variable controls, and these can increase or decrease the speed of your fan depending on its temperature inside the computer. The main point though is that your fan (or fans) must ALWAYS be spinning.

Is it OK to leave your computer on overnight?

It is always a good idea to turn off your computer overnight. For a start, it saves using your electricity unnecessarily. Sometimes, you may need to keep your computer on, for example for updates, security scanning and doing backups. Alternatively, you could do these tasks during the day if you are not planning to use your computer for certain periods.

Does turning off a computer wear down the power switch?

Prior to 1994 there were issues with power buttons breaking easily, which made people apprehensive about actually turning off their computer. Today, problems like that are a thing of the past. Of course, power buttons can still wear out, but the truth is, they have a lifecycle which outlasts many of the other components in your computer, so there is nothing to worry about.

Can turning off your computer cause soldering cracks?

No. Soldering can withstand changes of temperature easily. Most people have multiple TVs in their homes and these are turned on and off all the time, so you can see that it can withstand all the daily operations without any problems at all.

Can you prevent a power surge by turning off your computer?

No, a power surge will happen regardless of what you do with your computer. Having your computer power cord connected to a surge protector can safeguard a computer from an electrical surge. And thus from any potential damage. To prevent any damage to your computer during storms, blackouts or other power-related problems, use a UPS (uninterruptable power supply) which will provide you with power for an amount of time, during which the issues will hopefully be solved.