Why theory of original power usually is better than not the original power?

Why says below the sony cyber-shot dsc-w50 charger original power is usually better than not the original is the power supply. I want to say to the original power in relatively good, in fact, may not feel some difference. Usually load permitted input voltage to have a safe range, such as nominal value addition and subtraction 5%, an example of this is a lot of input 2.5 inches hard disk requirement is 5v deductions 5%. Laptop, too, if the input voltage is too big or too small will lead to protect circuit action, thus stop working. But in the protection circuit, before the action voltage circuit has internal laptop to work for lower limit or, in principle, has certain influence on device life but according to today's perspective, electronic components reliability has quite good, as long as it is in the scope of design, few will have a problem, life will not the short life than notebook, so this isn't the main problem.

The sony np-fh50 charger more important question is probably laptop data security, sudden automatic protection and stop working for the computer is very horrible things without the battery, particularly as many friends. Sometimes the computer puzzling restart also and relevant here. For the power supply for the original factory know to access is what kind of load that can easily calculate the power of nominal voltage and nominal current, namely power nominal voltage should meet the following two conditions, the first is the maximum current output nominal voltage minus power itself when needed greater pressure drop should load voltage, the second is the smallest 95% of output current design voltage minus power itself pressure drop is less than the required should load voltage 105%. However if you use is the original adapter, such as universal transformer and so on, these problems can't get serious consideration, this is the user can only from power parameter always try to get compatible, but each adapter resistance is different, nominal voltage permissible error might be different and nominal voltage output current definition of the variation scope of also might be different, even output ripple coefficient is small enough is not necessarily, if not careful measuring the output power relations with output voltage, in principle, but there is risk the risk is small, because as long as you choose big enough nominal current power won't appear too much internal impedance, ripple coefficient can also through internal transformation to reduce the notebook, so I said the original power usually is better than not the original power. This is the original power and ordinary power difference.sony np-bg1 charger