I am in need of 12v and i have an atx computer power supply lieing on my floor. ive been looking at this diagram
http://www.computers-n-robots.de/pictures/atx_pwr.gif
and making sparks for a while and i havent gotten it to power up yet does anyone know the trick?
Actually, connect the green one to any black with a paper clip (or something similar), then power it up.
Yes, I’ve tried this; it works.
Yep. Put a paper clip between the green and any black. I have a PSU that’s shorted this way to power my battery charger.
Just a quick word of warning - from what I’ve seen few power supplies designed for computers have internal breakers. So, whenever hooking stuff up to it (even if it’s like this) I try to add fuses/breakers in - the last time I didn’t I ended up melting a few wires… it wasn’t pleasant.
Tytus,
Several websites suggest the connections outlined above. Please be careful, the five volt supply is a high current device. Short the wrong wire to ground and the jumper may get very hot. These power supplies have internal fuses but generally only on the mains input. Also, without a load on the five volt power supply, the 12 volt power may not regulate very well. It depends on the supply design. Don’t open the supply if you are not familiar with switching power supply design. A large portion of the power supply and circuit board is at line potential, 120 VAC.
You should also be aware that many PC power supplies require some minimum load to turn on and to maintain regulation.
I have a similar problem, except, I have a board with only six pins in the molex connector, they are labeled +12v, -12v, gnd, gnd, +5v, +5v (yes, two +5v). I have tried an ATX and an AT power supply to no avail, bench supplies will get a warning beep (wrong power), I think that the bench supplies are to low an amperage. Any thoughts?
this doesnt work on power supplies that come with computers like dells, HPs, Compaqs, ETC… This will work if you use a power supply that you can pick up at a local store.