Actually power supply repair is rarely – less expensive to replace it with new. A defective power supply is usually thrown away, unless, of course, it is not a quality or expensive. In the latter case it is better to send it to a firm that specializes in the repair of power units and other components.
Most power supplies for protection against overload an internal fuse. If it blows, the power supply will not work. Opening the case, it can be replaced, but in most cases, replacement will not work – if not resolved the main problem, and a new fuse blows. In this case it is best to send the power supply to the repair shop.
Power PCs have built-in voltage regulation, which is calibrated and installed at the factory. After some time the parameters of certain components (components) may change, then change and the output voltage. If this is the case, you can use the configuration tools to re-establish the correct voltage values.
Several of adjusting the voltage is within the power source, usually they are variable resistors.
You also have to find for each strain your trimmer. This can be established empirically. You can mark the current positions of all the resistors, and then measure the output voltage, at the same time (in turn) slightly changing the position of controls of each trimmer unit until you see a change in voltage. If you change the position of controls trimming device, and the observed voltage does not change you, to restore the situation to its original position. (This is useful to label that you put before the experiment.) With this method it is possible to adjust the value of each voltage setting its value to the standard, ie, 3,3, 5 or 12 V.