Power Supply Unit
The power supply unit or, “P-S-U” as we system building nerds generally call it, is THE critical component of a computer but it is also so incredibly boring that many novice computer builders decide to cut corners here (of all places!). This may be due to a simple oversight on their part. They may just overlook the fact that computers are electronics, that absolutely everything a computer does is based on electricity! So, it follows that if the supply of this electricity is inconsistent, inadequet or in any other way unreliable the entire system will (if it works at all) be unstable, erratic, and potentially damage or destroy any or all components attached to the power supply itself (and this is exactly what happens)!
I don’t intend to be a fear monger here, but a bad quality PSU can absolutely destroy your investment plain and simple. It’s also incredibly simple to choose a good quality PSU that meets your system’s need so there’s no reason not to do so. If you don’t have the budget for a dependable PSU seriously consider not building the computer at all or reining in your CPU or GPU to free up some funds. Again, we’re aiming for a well balanced system here!
Of course if some people try to cut corners, some people also go in the opposite direction and get a power supply that (often) is rated to a wattage that is far higher than is actually needed for their system’s components. Wattage is also only one factor to consider when choosing an adequate PSU for your system. At least as important, if not more so, is choosing a PSU that has sufficient amperage for a given voltage.
To that end I highly recommend using a quality wattage and amperage calculator to give you a good basis as to what wattage and amperage you should be looking at for a PSU. To that end, I highly recommend the eXtreme Power Supply Calculator and have paid for lifetime access to their Pro calculator myself. Newegg also offers a wattage (not amperage) calculator, but whereas the eXtreme Calculator assumes you will be buying a quality PSU, Newegg assumes you will be buying a cheap PSU and adds about 100W onto their estimation. Newegg’s calculator also provides for far less customization, and far less details so all in all I definitely recommend eXtreme’s Pro Calculator if you can at all afford it!
As an alternative option if you can’t afford the Pro version of eXtreme or if you just want to double check the numbers that it’s giving you, you can also look for the wattage and amperage requirements for a given GPU and CPU from their manufacturers directly. If you take this route, and don’t also reference the eXtreme Calculator I would, to be safe and assuming a quality PSU, add about 50 watts to the PSU and about 5-10 amps to the 12 volt rail to error on the side of caution.
With those caveats out of the way, I will be looking at Seasonic manufactured PSUs exclusively. Seasonic is a highly respected PSU manufacturer, many of the big names that you may be familiar with rebrand Seasonic PSUs for much or all of their product line (Antec, Arctic Cooling, Corsair, Highscreen, PC Power & Cooling, Silverpower, & XFX). We will also only be looking at Platinum (or if not possible, Gold) 80 PLUS rated PSU’s. This is in keeping with our objectives for a power efficient system.
Quarter 1, 2012 Suggestions, Alternates, & Other Considerations
Suggestion: Seasonic Platinum Series 860W
First off, this is a higher wattage than I had hoped to find (once again I’m breaking my own ideals, but compromises are often required based on what is actually available for purchase at present). If however, you don’t mind losing a couple percentage of efficiency (and saving about $80) see my Alternate below.
With that aside, this is an incredible power supply! More than enough wattage and amperage (at any voltage) for any combination of components listed above. It has four PCI-E power connectors (two which would be needed for the GTX 560 Ti 448 alone) and is fully modular. In addition to these features, Seasonic’s Platinum Series 860W is rated to the highest efficiency (80 Plus Platinum) and has a seven year warranty!
Unfortunately, the Plantinum series from Seasonic doesn’t offer any lower wattage options as of this writing, if they do as you are reading this definitely run a wattage/amperage calculator and go with a lower wattage option if that is going to meet your system’s needs! Otherwise, if $220 is just too much for you to spend on a Platinum rated PSU that is more wattage (and amperage) than your system will likely need consider my Gold rated Alternate below.
Alternate: Seasonic X Series 560W
For a small step down in efficiency, but a fairly large step down in price (~$80) and you can get yourself a Seasonic X Series. The 560W or 660W should cover all your bases in terms of power requirements for most combinations of the components listed above in this guide.
The X Series has a five year warranty instead of the seven from above, but we still get the fully modular design. If you’re not going with the gaming PC, you can likely get an even lower wattage/amperage option. Again, this is why the calculator is nice as you know exactly what combination components you will be loading your system with (how many hard drives, exactly which GPU and CPU combination, how many fans, et cetera), so you can get the PSU dialed in exactly to where you need it. Thus possibly saving yourself some money if not time and headaches!