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Fortron Source FSP350-PN(PF) power supply review

Author: Vidar Langberget.
Posted : 2004-03-03 12:27:58.0
Category :

Power ratings

AMD published a Builders guide for desktop and tower systems document in 2002. In this document they specify power requirements for different set-ups. While some things have changed since mid-2002, we can still use the numbers as a guideline. According to AMD, a system builder should include a PSU that can cover at-least the maximum required power of the CPU plus 80% of the total maximum of all the other devices in a computer. That means that if the combined maximum power usage by from all your components is 200w, and the TDP of your CPU is 70w, you would need at least: 70w + 160w = 230w.

I have included their Power worksheet for a high-performance system. While the CPU is slow by todays standard, it has a TDP equal to the Athlon FX-51 (it was using an older fabrication process). The example system also has 2 harddisks, 2 optical drives, 3 memory modules and various other components. One component that would need more power than the stated would be the graphics card. In the example, it uses ~10w. A high-end card today consumes 50w-80w. So up to 70w should be added to the total.

Power supply ratings and normal power requirements

As you can see, the above system needs 280w x 0.8 = 242w. With a more powerful graphics card, that number rises to ~300w. Anyway, this PSU should be capable of running a high-end system without any problems.

ZDNet recently published another example of the power required by a high-end system:

As you can see, even the most power hungry system only requires 250w. Dont fall for the marketing trap and buy a $120 500w PSU, when a 350w might be more than sufficient. Just make sure you buy a quality PSU.

According to the ATX power supply specification, a PSU should operate within the following voltages:

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