kids, before you start discussing efficiency of a smps, learn what efficiency means in a smps.
like what components / process determine efficiency in a smps. what are the benefits of it (besides saving of electricity).
i think a smps having greater efficiency will run a bit cooler since less of power will be wasted as heat.
and in a smps heat is a major factor. the loads (Continuos) should be measured at near 50C levels, anything less than that, at say 25C, is jusy marketing hype. the temperature of the switching transistors and the coils has a great influence on the efficiency.
also the quality of each and every component in the psu has a great influence on the "quality" of the psu i.e. the ability to provide "Clean" power outputs.
Quality and Stability of power output at fairly high loads for extended period of time is a hallmark of a good psu.
merely going by the %efficiency in determining the value of a psu is wrong.
also many here do not really undertand the "Dynamic" nature of a psu. the loads in a smps psu are never constant (Testing with resistors = NA) and if you take a pc psu with multiple outputs, the variation of load is more since only one output is monitered and the values of all the outputs is determined by that monitered output (they are interlinked since basically they are from the same and only one transformer).
hence in a nutshell >% efficiency of a psu not only reduces power bills but also helps in keeping the psu components cooler which helps in stable and clean outputs.
but merely going by the figures provided by the manufacturer's or even some psu review sites (commercial bias) is another mistake many make.
get this in ur heads lads, there are very few smps which will provide clean stable power at their "Rated" output for extended period of time.
it is like "extreme overclocking". the figures and speeds have geek appeal but they are not practical or suitable for daily use due to the methods (increasing voltages etc.) and process (Dice, LN2 etc.) adopted for "extreme" o/c.
There is another trend visible where the aesthetics of the psu shield ( err the cover) is considered. many times i see a reviewer or a techie say " wow this psu looks cool", "sexy" etc ...
but what they dont understand is that a psu is not for sex appeal. as noted earlier each and every component in a psu plays an important role,right from a low cost resistor to the costly switching transformer, hence to increase the sex appeal many manufacturer's / resellers definitely save on the quality of the components to remain competitive.
hence before talking about efficiency and making judgements many here would be well adviced to actually open a psu (disconnect from mains first) and learn to identify the components and their functions.
hyeah:
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