If your goal is to have a quiet computer, your best bet is to obtain a quiet power supply. Fortunately, there are various kinds available, and most cost about the same as a standard power supply. Having this kind of product may enable you to sleep or talk on the phone in the same room as your computer, both of which can be difficult with a noisy desktop or laptop. Before you shop, consider details like wattage, efficiency of the fan, and design.
Prior to purchasing a quiet power supply, you should find out the wattage compared to what you need. This is because a power supply that is too heavily loaded or not loaded enough is not considered very efficient. If you get a power supply that has high wattage and plan on using it for your desktop that spends most of its time idle, or that is lightly used, you will likely notice a lot of noise. On the other hand, if your computer uses more watts than your power supply is built for, you will also probably observe more noise than you would like, and your computer could also overheat and malfunction. For this reason, it is crucial that you compare the wattage on the power supply to what is recommended for your computer's processor and motherboard.
The fan is a major component of any power supply since it can be quite noisy or completely silent. You should look for power supplies that feature particularly quiet fans, but if you cannot find one, you can always replace the power supply fan with a quieter one if you have the experience. Many quiet fans are larger and run slower than others, which is what makes them nearly silent. You can also consider a quiet power supply that features no fan, but instead relies on an internal heat sink to cool the system. Just keep in mind that this kind of quiet power supply may cause the computer to run hotter than it should, which means it is usually only good for systems that require low wattage, and will not be overloaded.
Design is important when it comes to choosing most computer parts, especially when it comes to power supplies. If you want a computer that is as quiet as possible, you should look for a power supply that is designed to allow easy airflow. This is especially true if you opt for a fanless quiet power supply since the computer may run the risk of overheating if air cannot move freely through it. Such a design is not usually appropriate for a high-end gaming machine, for example.