Another component that deserves your full attention in order to be not deceived is the PC power supply (PSU). For entry-level PCs, with on-board video or using low-end video cards like GeForce 6200 or Radeon X300 the power supply isn’t a critical component. But if you have a video card that requires an extra power supply connection (from GeForce 6600 GT up, from GeForce FX 5700 Ultra up, from Radeon 9700 up and from Radeon X700 XT up) choosing a good power supply is essential.

The main problem is that the majority of power supplies available on the market are wrongly labeled. We are tired of facing 180 W power supplies being sold as 400 W ones. And this isn’t an error made by the store: on the power supply label it is really written ”400 W“. So, you can buy one power supply like this one believing that you are really buying a 400 W power supply and start facing ”freezing“ and reseting problems on your PC because the power supply isn’t being able to provide enough current to your PC.

To know the real power capacity of a power supply you need to add up the individual power capacity of each power supply output. On a given power supply you can find the following power capacities written on its label: 100 W (for +5 V and +3.3 V outputs), 96 W (+12 V), 2,5 W (-5 V), 6 W (-12 V) and 10 W (+5VSB). Adding up these values we could find that the real power capacity of this power supply is of 214.5 W. Amazingly enough this power supply was sold as ”400 W“.

If you are buying a high-end system, our suggestion is that you don’t save money on the power supply and choose a ”branded“ one (also known as ”real power PSUs“), like TTGI, Thermaltake, Cooler Master, Enermax, OCZ, Seventeam, just to name a few.

Learn more about this subject by reading our Power Supply Tutorial.