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Power supply ?'s
aj6500:
I have an ATX power supply that I'm going to use to power a 12v amplifier. I have a couple ?'s for those who know more about them than I do. I'm experimenting w/a 200w, and I have a 500W on order to actually power the amp.
I have 2 4 wire harnesses exiting the supply, 1 red, 1 yellow, and 2 blacks. Correct me if I'm wrong, red will be +12v, black will be ground, what is yellow?
I also have 1 large harness that plugged into the motherboard w/20 misc. colored wires. I'm guessing that some of these are also DC out, but I'm guessing they are of lower voltage and of no use to me for this project. Will any of these be a 12v out? I need to gather all possible 12v sources as they will all be connected to the 12v input on the amp to increase the combined wire size to the amp.
I would like my PC to turn on the 2nd power supply when it turns on. I plan to run a jumper from the remote switch on the back of my cab that turns on the pc to the power supply. The PC and the one I pulled the PS from use momentary buttons for power. How do I find which wire to connect to on the main harness to make this work?
NAH:
I have 2 4 wire harnesses exiting the supply, 1 red, 1 yellow, and 2 blacks. Correct me if I'm wrong, red will be +12v, black will be ground, what is yellow?
on the two molex connectors, red is +5 V, both blacks are ground, and yellow is +12 V
paigeoliver:
--- Quote from: aj6500 on April 25, 2003, 04:58:47 am ---I have an ATX power supply that I'm going to use to power a 12v amplifier. I have a couple ?'s for those who know more about them than I do. I'm experimenting w/a 200w, and I have a 500W on order to actually power the amp.
--- End quote ---
You may very well fry the power supply for operating without a load on the +5 circuit. Get SOMETHING that draws +5 volts as well.
BobA:
This link has info re the ATX type power plug that you will find on most newer PS. It should answer your question about voltages and the power control signal.
http://www.duxcw.com/faq/ps/ps4.htm
If you are not going to be using the 5V from the PS then the minimum 5V load should be connected. If it requires 1A of load to stablize the 5V then a 5 ohm power resistor will provide a 1A load to be safe get a 10W resistor. The value available will probably be 4.7 ohms if I remember my resistor values correctly.
Good Luck
BobA
aj6500:
Ok, if I strip the motherboard out of my old computer, strip CPU/memory... from it, and plug the main harness into it, but use the 12v outputs from the power supply to run the amp, will that keep the power supply stable and still provide the voltage I need?