Old Computer Power Supply

Hey all, I got a old computer and I decided to get some components from it. The power supply was one of them. I saw that if we connect the green wire with any of the blacks, I could make the PSU start, but that isn't hapenning. But whenever connected to the motherboard it works fine. The model is PDP-116P from COMPAQ with an output of 24 pins. Can someone help me to get it working?

This is sometimes Grey but Google the part number for a full diagram. I have done 2 of these now , one powers my LED strip lights my switch on the wall simply connects the PSU on so no voltage going through.

The other is on my bench with dedicated 12, 5 and 3,3 volts lines.

Google "hacking computer power supplies".

Following is what one site says; 1. Older power supplies must have the Ground and Green power shorted. 2.. Some newer power supplies must have zero volts (grounded?) on Orange/Brown wire. 3. Alternately a load resistor on 5V line may be needed.

jaylea: This is sometimes Grey but Google the part number for a full diagram. I have done 2 of these now , one powers my LED strip lights my switch on the wall simply connects the PSU on so no voltage going through.

The other is on my bench with dedicated 12, 5 and 3,3 volts lines.

I tried also with Grey and with the white (because is where green should be). All attempts failed.I google it and it always says the same (green wire to ground).

x50505: Google "hacking computer power supplies".

Following is what one site says; 1. Older power supplies must have the Ground and Green power shorted. 2.. Some newer power supplies must have zero volts (grounded?) on Orange/Brown wire. 3. Alternately a load resistor on 5V line may be needed.

  1. I googled that and nothing new appears.
  2. I tried ground on orange and brown wires, all of them, nothing happens.
  3. I don't tried that but I don't know exactly how to do it.

Should I go to a hardware store trying to get some help?

I suspect its looking for some resistance just like Iphones do so they only work with legit chargers. I have not had this problem. plug it back into the main board of the old PC then try the green and any black if it fires up then it wants resistance somewhere.

jaylea: I suspect its looking for some resistance just like Iphones do so they only work with legit chargers. I have not had this problem. plug it back into the main board of the old PC then try the green and any black if it fires up then it wants resistance somewhere.

When it's connected to the motherboard it works just fine, but when it's unpluged, no longers works.

Any ideas to "fix" this?

josecoelho: Any ideas to "fix" this?

Here's a page full of suggestions: http://lmgtfy.com/?q=start+atx+power+supply+PDP116P

I did a lot of search before creating the topic, so I checked all that already.

Im sorry I don't know but www.the12volt.com/ might be able to help. there a bit sarcastic and assume you know more than you might but if you ask nicely im sure someone there can help.

I never wanted to look sarcastic or anything near that, if I looked I apologize for that. I will try get some help at The12Volt, thanks for the tip.

No you misunderstood me. I didn't mean you look/sound sarcastic. my mistake for not being clear.

You must have an minimum load on 5 volt and/or 3,3 volt. Try with 5 to 10 ohms.

And Green to black.

Pelle

3. Alternately a load resistor on 5V line may be needed. 1. I googled that and nothing new appears. 2. I tried ground on orange and brown wires, all of them, nothing happens. 3. I don't tried that but I don't know exactly how to do it.

RE3: Take about 40 ohm 5W resistor and connect one end to +5v, the other to ground, or better yet, take a computer fan and connect it instead of resistor.

jaylea: No you misunderstood me. I didn't mean you look/sound sarcastic. my mistake for not being clear.

I'm sorry about that, sometimes being a non native speaker of english might be tricky.

Pelleplutt: You must have an minimum load on 5 volt and/or 3,3 volt. Try with 5 to 10 ohms. And Green to black. Pelle

I don't have any 5-10 Ohms resistor, the lower is 100 Ohm, but all are 1/4W or 1/2W, that would do the job?

x50505: 3. Alternately a load resistor on 5V line may be needed. 1. I googled that and nothing new appears. 2. I tried ground on orange and brown wires, all of them, nothing happens. 3. I don't tried that but I don't know exactly how to do it.

RE3: Take about 40 ohm 5W resistor and connect one end to +5v, the other to ground, or better yet, take a computer fan and connect it instead of resistor.

I don't have any 5W resistor, but I'll try with the fan.

Thanks for the tips everybody.

x50505:
or better yet, take a computer fan and connect it instead of resistor.

A computer fan runs from 12V, not 5.

Or a 12 volt 5 W lamp (from a car)

Pelle

Pelleplutt:
Or a 12 volt 5 W lamp (from a car)

Connected to the 5V line?

Remember that as you previously stated, it is the 5V and/ or 3.3V lines in the power supply, that are regulated, not the 12V line.

21W (turn indicator) lamp would be more appropriate.

I will try with something that works on 5 or 3.3 volts, like a lamp or a motor, if I can't get none of that, I will try with a resistor.

Hi again, I found this when doing some more search: http://www.experts-exchange.com/Hardware/Components/A_3940-Use-a-Compaq-200-Watt-Power-Supply-PSU-as-a-second-power-source.html. I decided to try it and the PSU turns on, but after a few seconds, it turns off again.