After needing a 12v power supply i decided to create one from an old atx power supply that was working somewhat.
I had lying around a couple of old atx power supplys and this one was the nicest of them all, all i needed to change was:
As you can see on the scematic, this is how everything is wired inside the atx psu.
Thing that needed to be added:
I forgot to take pictures of all the steps but you get the idea, remove some wires, change around other wires, connect new ones, heatshrink were needed and you get a beautiful looking atx power supply. The atx short circuit and other protection features were kept intact for reliability and accidental mistakes.