Viper's Lair has posted a review on the Thermaltake Silent Purepower 420W PSU

Many manufacturers can claim "x" number of watts, but what you will want to be concerned with is the combined output of the +5v and +3.3v rails, which is what items such as your CPU, AGP/PCI cards, and memory needs, as well as anything plugged into the floppy power connection. If possible, you'll want at least 200W combined. The Purepower has 220W, which is pretty good.

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