When we a buy a new computer the first thing most of the people ignore is a smps or powersupply. This is a very common mistake made by them and they usually settle for the default power supply that comes bundled with the computer cabinet or casing thus compromising on quality,performance and stability. They can work normally but can fall under heavy load and voltage fluctuations. So if you want your computer to function properly and want performance and stability under heavy load then you have to go and purchase a separate branded smps. Also it can fulfill your needs to have a middle range graphics card on your system to play games as well. The Power Supply forms the one of the most important part of your computer.
A SMPS (Switched-Mode Power Supply) or Computer PSU (Power Supply Unit) is a unit of your computer that supply power or electricity to all your components on your computer. It is designed to supply proper voltages and current that is needed by various devices like cpu, motherboard, hard disk, optical drive, graphics card or any other pc component.
How to choose a good SMPS ?
First thing is that do not get fooled by the SMPS Watt rating. This a very common mistake done by the people. A good 300 Watt smps can easily beat a cheap local branded 500 / 600 Watt SMPS. The very first thing that you should look for in a SMPS is the 12 volt amperage reading. There is a voltage /current chart printed on every smps, on that chart look for the current/amp below 12 volt reading and make sure it is at least 30 amp [if it is a dual rail smps then the each rail i.e. V1 and V2 both should have at least 16A to 18A current on it individually]. If it is above 30 amp then it can be considered as a good smps for a system with basic configuration. If you want a SMPS for gaming then the 12V Ampere should be more than 35A.
12v rail is responsible for providing power to the major components in the computer i.e processor, motherboard, graphics card, hard disks. So greater the current rating of 12v rail the efficiency and stability is bound to be good. High end SMPS’s have either single or multiple 12v rail and have more than 40 amp current on it. So it is the most important factor when you buy a SMPS. Besides this you can also look for the smps weight, by feeling it in your hand, heavier the smps the better heatsink it will have, means a better cooling and more stability under heavy load.