How to select the power supply?

An example to the AcBel IP Power
AcBel IP Power series can be said that the name brand cheap, but also all the rage, the purchase by the public.
But at the same time the power of the IP series also exposed some problems: the conversion rate is not high, excessive ripple output and poor cross-load. There is always let everyone ills
The AcBel been accustomed to 25 degrees calibration of output power, such as the IP470 is he the subject of the rated power is 420W, but AcBel is standard at 25 degrees,
We all know that the hot weather, a lot of people at home at room temperature more than 25 degrees, 35-40 degrees issued by the temperature even on the machine, power is a very common thing
To 35-40 degrees, IP470 rated power output is not the same, 420W should be discounted at this time is estimated only up to 300W of power to use.
Wow! ! There is such a statement? Yes, the power is so complex, various manufacturers have the manufacturers standard Chennai its Ho?
That being said, the IP470 whether can not be used? Definitely not! IP470 in the ordinary players in the eyes it is a high-end (of course, in the eyes of a small number of the best players this is the rubbish one)
But you do not see the city to sell the city's computer basically Han stuff, and then take a look inside the low-end brand of Han stuff? Then look back at the IP470 whether ordinary people in the high-end.
This power professionals to get into the test room into incubators, access load source, oscilloscope, casual look also know that the grade is poor.
Is indeed poor, and this is recognized.
However, we may not know, professional equipment even if it was so bad, but we use them how to feel it is relatively less problems?
Single power supply test so bad, is not equal to the entire platform testing so bad, because the hardware such as motherboards and graphics cards have their own independent power supply system, administered by the power output ripple less than satisfactory,
But through its own capacitor or an independent power supply system will convert and adjust their work to maintain normal. Some of the hard drive design also leave room for much sensitive to the voltage a little fluctuation of the point of inevitable accident.
The power supply is a complicated topic, toss the industry for so long are not fully mature program, basically the program available in the market is not the shortcomings in this regard is defective in that regard, sometimes the manufacturer is feeling the stones.
So I chose the power to choose some with the entire platform can be enough, no need to be too afraid, the computer is a set of equipment, not a single power supply in the battle, after all, there are other hardware circuit design for your checks to those XX capacitor the XX circuits where the use?