For most there are two main reasons for paying the premium price to purchase an 80+ rated PSU; the eventual money savings from lowered power costs and to reduce your carbon footprint by using a more efficient PSU.  [H]ard|OCP put the first reason to the test, examining several cases of usage for PSUs of differing wattage and usage.  As well, they point out the issues with some ratings, as PSUs that are labeled as 80+ Platinum only deserve a Gold rating in most usage scenarios.  Their findings are based on theoretical usage patterns, it is hard to imaging a PSU operating at 50% load day after day, but this will give you an idea how many days or years it will take for you to start seeing a return on your investment.

"A HardOCP editorial about the 80 Plus program and how it is changing the computer power supplies you are buying. Is this good, bad, or ugly, and should you care? Did you know that you paid for that 80Plus rating on your shiny new PSU? Certainly PSU efficiency is a great thing, but what about the rating system?"

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