Not for computer use, but I need a high current power supply that can deliver 15+ amps at 13V or above (ideally 14V, but no more than 15V). All the high current power supplies are expensive, so I was wondering if anyone knows of a way or could point me in the right direction to modifying an existing ATX power supply to output 14V on the 12V rail. The great thing about switching ATX supplies is that they are cheap and capable of high currents on the 12V rails.
I've come across some power supplies that when taken apart, there is a variable capacitor that you can turn to increase/decrease the voltage in a tiny increment.
Also, here is a project of exactly what I want to do, except I dont really know what is going on:http://www.webx.dk/oz2cpu/radios/psu-pc1.htm
Ideas would be great.
Is not to complicated to get 14V you just need to find the voltage feedback where are usually two resistors acting as a voltage divider (some time you may find a variable resistor if you are lucky) you just need to change the value of one of the resistors in order to get a different voltage on the 12V line. Probably you will need this 14V to charge batteries
If you don't already have the power supply then you can buy from ebay something like this link
they already have a variable resistor so you can set to 14V you can buy the 12V or 15V version and set your desired voltage.