Power Supplies Buying Guide
A power supply is the most important part of any comp...
Power Supplies Buying Guide
A power supply is the most important part of any computer system, without a good quality PSU in your system you can run into problems and possibly even damage your system. Many people don't pay as much attention as they should to their PSUs, this can be a hazardous and possibly disastrous mistake.
If you're building a system from scratch you'll most likely buy a case as well, some cases do come with basic power supplies, and honestly they're usually not very well made or powerful enough to handle higher end systems. Of course there are exceptions to this, you can get a good quality PSU included with a case at times, you just have to look for a reputable manufacturer. Many times though if you're building a system you'll buy everything separately including the PSU and you'll want to make sure you purchase one from a reputable manufacturer.
The PSU can be considered the heart of the computer system, it provides power to all of your components in order to keep everything running smoothly. You'll want a power supply that provides quality, clean and stable power to your system. Stability is the key factor really, you'll want the power supply you choose to provide stable, reliable power to all of your components, any major fluctuations in the rails can potentially cause damage to your components and of course we don't want that happening at all.
When we are talking about ATX or desktop power supplies there are two main types, Modular and Not-Modular.
Modular styles are types that allow you to plug-in cables as needed to reduce clutter in your case, and to allow you to add cables as need be for upgrades. Modular power supplies can also be truly modular where every cable can be removed, and they can also be semi-modular where the main power connections are hard wried and the component cables are the ones that can be removed only.
Non-Modular is just that, every cable or connection is hard wired into the power supply and not removable. Any cable that you don't use for your system will just be hanging around in your case or need to be placed out of the way to keep the case neat and to promote good airflow within the case.
There are also specialized types of ATX power supplies, these usually are for smaller form factor style or SFF cases, they look essentially the same just only smaller.
When you're looking at the purchasing a power supply it can be confusing with all of the technical jargon and other information that companies list about their products.
Many PSU makers are trying to go green, this not only helps their image but in the end helps the consumer as well by making a more efficient power supply they're in turn saving you some money. You'll often times see power supplies listing the fact that they are 80Plus certified, this means that the PSU in question has been independently certified by the ECOS 80Plus program to meet or exceed 80% efficiency, so obviously this is a good feature all around.
What is the 80 PLUS specification?
The 80 PLUS performance specification requires multi-output power supplies in computers and servers to be 80% or greater energy efficient at 20%, 50% and 100% of rated load with a true power factor of 0.9 or greater. This makes an 80 PLUS certified power supply substantially more efficient than typical power supplies and creates a unique market differentiation opportunity for power supply and computer manufacturers.
Something else you'll run into is PFC, Passive PFC or Active PFC, which stand for Power Factor Correction, and it's kind of what it sound like it is, in simple terms it corrects the power flow to the system and makes it more efficient. Active PFC is the better of the two, but it usually adds more overall cost to the unit as it needs more specialized parts to the PSU. For the most part though the difference in price is negligible, and when it comes to higher end power supplies, active PFC is a standard feature. Which is better active or passive? Active is always going to be the better choice as it's normally going to provide a PFC of .9 or above, which means it's going to be at least 90% efficient
You might also see an SLI or CrossFire Certification or possibly both listed in the features of a power supply as well. This means the PSU has been certified by Nvidia or AMD to be used with their video card in dual card configurations, something to keep in mind and look for if that's the kind of system you are building.
Finding a good quality power supply can be hard to do, but if you buy from a well known manufacturer you'll most likely not have a problem getting a reliable and stable PSU for your system. There is a way to find out exactly who made your PSU though, but normally you won't have access to this information until you get the actual PSU in your hands. There is a UL or Underwriters Laboratories number on the specifications label on the unit, it's usually under the UL log, which is a backwards R and a U combined. You can take this number and go to the UL database on their website and find exactly who made the PSU you have in your hands. Many companies sell prower supplies and often they are re-branded with their own name, for example you could purchase an Antec branded power supply and look up the UL number to find out it was made by Seasonic.
Sometime you can find this information is power supply reviews you find online, many sits will look up this information and provide it to their readers so they know exactly what they are getting.
Basic things to look for when purchasing a power supply:
-If it's a multiple 12v rail power supply look for a minimum of 18Amps on each rail, you're better off with more though really.
-If it's a single 12v rail style power supply look for a minimum of 60Amps across all rails.
-Look for well known manufacturers as you'll know you're getting a quality product.
-Make sure there's enough connections for your current and future needs, a power supply can last quite a while and be rather expensive, so you won't want to have to upgrade your PSU when you add more things or upgrade your system. Many newer video cards today require two PCIE power connections which can be six or eight pin, make sure there's enough for your needs.
-Check out the included cooling, especially if it's a large wattage power supply, you don't want a small fan trying to cool your PSU, it won't last and it won't do a good job.
-Noise levels are another possible characteristic to look for, some people might not care about noise levels, but others might like a silent system, many manufacturers list sound levels in the specs of the product.
-Size can also be an issue when purchasing a PSU, with larger wattage power supplies the physical size of the PSU can be very large, you'll have to make sure you're existing case can fit the PSU easily.
-Modular or not? Modular power supplies are nice, especially for systems with not many components in them, they can help keep the wiring clutter down to a minimum. Modular PSUs are also convenient in that you can just add a new cable to the power supply as need be when you add more components or upgrade your system. Of course there is the debate of Modular vs Not, at this point though the technology has progressed to the point where, if you buy from a reputable manufacturer, there really is no difference between them.
One of the best ways to find a good power supply is through reviews online, many sites use expensive and sophisticated equipment to stress and test power supplies to make sure they can handle the loads that they claim to be able to. You'll also learn what they look like of course, and how reliable and stable they are as well. For something like a power supply, reviews can be an invaluable source of information about the product.Close