Buying a Used Power Supply

By Steffany Kellam

Power supply units (PSUs) are the last components to wear out on any computer system, making them an excellent option for reuse in new builds. However, purchasing used PSUs comes with its own set of risks and considerations.

Wattage should be your main consideration, but there are other specifications worth keeping in mind as well.

1. Check the condition

Power supplies are essential components of computers. As electronic devices go, power supplies supply energy needed to power them; but as with all electronic components, their performance can malfunction and cause serious problems for machines that they power. By understanding the symptoms associated with bad power supplies and learning how to recognize them quickly before problems worsen further.

An obvious sign of PSU failure is when it fails to switch on. Sometimes this simply means it won’t function at all and must be replaced immediately. You should also pay attention to how your PSU sounds; clicking noises could indicate overheating or short circuiting issues within its components.

PSU failure typically shows in a sudden decrease in performance. Over time, PSUs lose up to 20% of their maximum wattage every year they’re used.

PSUs can also be damaged during shipping conditions. Though thick layers of packing foam should protect its equipment, if the PSU is dropped or slammed during shipment it could crack PCBs, which in turn cause failure of its power source and potentially other components.

As a general guideline, it is advisable to review the warranty of a used PSU. This can give an indication of its longevity; higher-end models typically last longer. Furthermore, usage will play an important role in its longevity as well.

2. Check the warranty

At all times, it is wise to purchase a high quality power supply when building your own PC. When buying used, be sure to read through and understand its warranty carefully as this will give an indication of its usage and whether there have been any defects or issues with it.

Most PSU’s come with one to five year warranties provided by their manufacturer, with such policies calculated according to anticipated lifecycle calculations and field return data from field returns, in addition to taking into account repair/replace costs for units that exceed their warranty periods; although most power supplies should last well beyond this point.

If you are uncertain of the condition of a used power supply, using a multimeter can help determine its status. This electronic device measures electrical current such as voltage (volts), amps (amps) and resistance (ohms). In addition, you can inspect motherboard lights or listen for fan noise in order to test this PSU.

Checking the type of connector is also vitally important. Some computers such as Dell use special connections that cannot fit with a standard ATX plug and may cause serious harm to both power supplies and motherboards.

PSUs with sleeved cables may also be more aesthetically pleasing and make wiring easier, without obstructing airflow in your computer. Check whether any new PSU you purchase includes these; typically they cost more than un-sleeved ones and usually signify higher-quality and performance improvements.

3. Check the cables

Power supplies (also known as PSUs) are the hub of any gaming rig, providing power to every piece of hardware in your rig. Without an effective PSU, nothing would work, which is why it’s vital that any used PSU you purchase comes equipped with all of the cables you require – including 24-pin ATX for powering motherboard and 8-pin CPU and PCIe connectors needed by graphics cards; plus it should have an air flow fan to keep your power supply cool and quiet.

Modern PSUs often allow users to select which cables they require for their build, making the case cleaner while adding cost and resistance due to an abundance of wires. Therefore, it’s wise to inquire whether or not your PSU is modular before making your decision. This factor should play an essential part in your decision process.

As with the cables themselves, another critical consideration when inspecting cables is damage and defects. This includes broken strands not making contact with your PSU which could result in short circuits and even fire. Furthermore, using a multimeter to measure resistance allows you to assess if conductors remain undamaged by comparing resistance measurements between cable conductors and multimeter leads (minus lead resistance) of multimeter test leads (including any lead resistance of multimeter leads)

4. Check the voltages

If you’re purchasing a used power supply, be sure to carefully examine its voltages. These should be clearly printed on the back, and tested using a multimeter. Each rail serves a separate component such as motherboard or USB ports – if the voltages don’t match with what was advertised for that power supply it could indicate it has failed and requires replacement.

Checking the output voltages of a power supply is also vitally important. A multimeter can be used to check each one; however, older power supplies without built-in voltage readings may prove more challenging to utilize as you must also ensure all manual switches have been set correctly to control output voltage outputs.

Your system requires a power supply with high output voltages that is suitable for it. Ideally, this should provide sufficient output power to support both your motherboard and any additional components you are using without overburdening its internal parts – however a PSU that is too powerful can damage those parts over time.

As part of your search, it is wise to look for a power supply with an efficient efficiency rating. This measures how much electricity the PSU converts into usable power versus how much heat is wasted as heat. A higher efficiency rating can save money over time by decreasing how much power you need to purchase and use; additionally, making sure your PSU includes failsafes can protect it against sudden changes in power such as spikes and surges that could damage other components in your system.

5. Check the temperature

Temperature fluctuations within a PSU should never be overlooked, yet overheating can pose serious threats to its internal components and ultimately ruin them. To check its temperature you can use either an online tool or multimeter; if unfamiliar with how to do this it’s best left for professionals.

Wattage of power supplies is another factor worth taking into account, to ensure they meet the demands of your PC build. A wattage calculator can help determine how much wattage is necessary and which model to purchase.

Make sure that the PSU you buy is not overloaded. Doing so could cause damage or overheating; one way of avoiding this scenario would be asking the seller what kind of PC they used it in; high-powered overclocked PCs put undue strain on PSUs and may warrant passing up such deals.

While power supplies may not be the most exciting component in a computer, they’re nevertheless essential. Without working PSUs, your PC would quickly cease functioning – so before purchasing used PSUs be sure to follow these tips for quality power supply that can meet all your computing needs for years! We wish you the best of luck in finding what will hopefully become an amazing supply unit!