first of all I am a real novice in electronics but according to my circuits and electronic classes I think this should be possible:
I want to use a 4-pin ATX cable as a power input in order to generate 24 outputs. Basically, my idea consists in using zener diodes.
Having 12Volts as input and then a 5Volts zener diode I should be able to have a +5V output, then connecting this output to a 3.3Volts zener diode I should be able to have a +3.3V output.
Here's a circuit I've barely drawn:
My question is how would I deal with the -12V output? And also once all voltages are tested and wrapped in the 24-pin connector, How safe would be connecting a motherboard to this result?