Selecting a Computer Power Supply

August 17th, 2008 admin Posted in Gaming PC's |

Choosing a computer power supply can be easy, provided that you don’t fall for the common mistakes. One of the most common mistakes people make when building their own computer is to neglect the importance of computer power supply. Tending to cut down their budget on it and get the cheapest one available. If you really care about the longevity of your computer system this advice should help you put in some effort to choose the right power supply.

Power Rating
The problem with today’s PC users is that they have not realized how much more powerful a computer has become, and because of that how much more power it needs Here is a table listing the parts for your computer and how many watts are generally devoted to each of them:

Computer Parts

Watts
Motherboard: 15-30
Low-End CPU: 20-50
Mid To High-End CPU:40-100
RAM: 7 per 128MB
PCI Add-In Card: 5
Low To Mid-Range Graphics: 20-60
High-End Graphics: 60-100
IDE Hard Drive: 10-30
Optical Drives: 10-25

Add up the power required for your system and get the power supply with a power rating higher than that required power. If you are building a high-end gaming computer, chances are you’ll need a 600 - 650W power supply.

Mean Time Between Failure (MTBF)
This is essentially the lifespan of the power supply; it represents the average hours the power supply can perform before it fails. Most power supplies will have MTBF ratings of 100,000 hours or more, but know that these figures were not collected from actual real-time testing. Typical ratings are based upon the comparative failure rates of the power supply’s individual components.

Short Circuit Protection
When choosing a computer power supply, make sure that it is equipped with a short circuit protection feature. This is a preventative action, making sure the computer parts don’t draw excessive currents, which could lead to its internal chips being burned.

Low Noise
The main reason a power supply is noisy is its inability to dissipate heat fast. The fan has to work on overdrive to maintain the required temperature. When choosing a computer power supply, make sure that it comes with a big powerful 140mm fan or two 80mm fans to effectively dissipate the heat and avoid any issues.

Load Current (Maximum and Minimum values)
Each computer part requires different voltage and current to function. It’s important that the power supply can support the various voltage levels and the ones currently being supplied. Some terms to remember:

Maximum load current - The maximum current that the computer part can accept for a particular voltage level.

Minimum load current - The minimum current the computer part needs to be functional.

If the part is not getting the minimum load current from the power supply, the power supply is in trouble.

Form Factor
Most of the power supplies in the market are of the ATX form factor. However, if you are using a micro ATX computer case, make sure to get a micro ATX power supply, otherwise it won’t be able to fit inside the case.

Recap
Power supply is a computer part that you must pay attention to. When choosing a power supply, always go for one that has a higher power rating than what your system needs.