CPU Power supply?

hmpit_ags2006 · #1 10/16/2006, 04:10 PM

So I have 2 laying around that work on cpu's but I can not get them to work with just some fans and led's hooked up to it. I am probably going about this all wrong but I was wondering how y'all have them working.

Thanks,
-G

Qwiv · #2 10/16/2006, 05:23 PM

They should work fine. Are you sure you are using the 12v. Should be using the yellow and the black wire on most computer power supplies. The Red is normally 5v+, White 5v-. Black is ground, Yellow is 12v+, Blue is 12v-.

hmpit_ags2006 · #3 10/16/2006, 05:27 PM

they are molex 4 pin connectors

hmpit_ags2006 · #4 10/16/2006, 05:31 PM

Gixxer2202 · #5 10/16/2006, 06:13 PM

When you plug the fans in the power supply they dont just come on otherwise you would have them spinning 24-7 you need a mobo in order to control the power or an adapter to trick it as if it was in the mobo. I just found some old 12v power converters and wired them to the fans. I have 4 120's in my canopy.
Good Luck
Scott

hmpit_ags2006 · #6 10/16/2006, 06:50 PM

Yeah I guess I need an adapter or something cause nothing comes on. Do you know where one is? I was going to put the power supply on a timer so they wouldn't be on 24/7. I already have 2 power supplies so I figured that I could just use them since I have them just lying around.

Qwiv · #7 10/16/2006, 07:03 PM

Ah, some power supplies don't power up unless they sense they are connected to the motherboard. Check out this link
http://www.wikihow.com/Convert-a-Com...b-Power-Supply
It should help you figure out what wires need to be connected to get it powered on.

Hope this helps.

hmpit_ags2006 · #8 10/16/2006, 07:33 PM

Thanks, that is a lot of work. I was kind of hoping that there would just be something I could connect to (adapter) to make this work.

Qwiv · #9 10/16/2006, 10:33 PM

Just read the part about getting the power supply to power on, you don't need to do the whole thing.

Here is the quote:

"Some newer power supplies will have "voltage sense" wires that need to be connected to the actual voltage wires for proper operation. In the main power bundle (the one with 20 wires), you should have four red wires and three orange wires. If you only have two orange wires, you should also have a brown wire which must be connected with the orange. If you only have three red wires, another wire (sometimes pink) must be connected to them."

Altpers0na-old · #10 10/16/2006, 11:36 PM

i have one hooked up for a 12v supply,

on the large connector, locate what i hope is the only green wire.

connect that to a push button along with ground (any black wire from that connector) and it should go... push once to turn on and hold in for a few seconds to turn off.

an 'at' power supply has its own switch.

curtisk · #11 10/17/2006, 02:42 AM

You can go to Walmart in the electronics section and find a power supply like this one

Make sure it's rated at 12v output so ou can get the maximum on your fan speed

Cut the round connector at the end and splice your fan wires to it and tape them up. And you're ready to go. I just asked the same question here and AZDesertRat was quick to respond...

hmpit_ags2006 · #12 10/17/2006, 04:40 AM

I know I can hook them put to random adaptors but I was just hoping that I could hook them up to PC power supplies without much effort.

Simon Terry · #13 10/17/2006, 10:05 AM

I had to register just to post this, but you can use the PC power supply just fine.

Assuming it's a newer ATX power supply just bend a paperclip around into a small U shape. On the big ATX connector stick one end of the paperclip into the end of the green wire and the other into any of the black wires. plug the power supply in and you're golden.

As posted earlier you could attach a momentary switch to the green wire instead, but this will at least get you up and running.

Hope this helps,

Simon.

CraigG · #14 10/17/2006, 12:04 PM

Quote:

Originally posted by Simon Terry
I had to register just to post this, but you can use the PC power supply just fine.

Assuming it's a newer ATX power supply just bend a paperclip around into a small U shape. On the big ATX connector stick one end of the paperclip into the end of the green wire and the other into any of the black wires. plug the power supply in and you're golden.

As posted earlier you could attach a momentary switch to the green wire instead, but this will at least get you up and running.

Hope this helps,

Simon.

Exactly. You main mobo connector (20 or 24 pin) is the one you need to figure out what pins you need to use. On a 20 pin connector, the 4th pin over from the left (Green) and fourth pin over from the right (Black) are usually the two used to complete the circuit to power the fans. I have three PS's that I have used for various things, such as lighting and fans. It works great.

Simon Terry · #15 10/17/2006, 01:42 PM

Actually all of the black wires on the motherboard plug are grounds. Pick any one

They make great 12 volt power supplies for all sorts of applications around the aquarium. Fans, relays etc.

Plus, any self respecting geek should have at minimum 3 unused power supplies around the house

(guilty as charged)

-Simon

musty baby · #16 10/17/2006, 03:06 PM

It's really not much effort at all. You have to stick a wire between two connections on a different harness of the power supply, then and only then will the unit power on and allow you to run stuffoff of the supply. Have done this before to fit extra power supplies into computer cases.

Oops, guess the last three posts summed that up well. It's easy. Just tape over the paper clip and you're good to go.

Humidity around an aquarium may become a problem, though.

musty baby · #17 10/17/2006, 03:07 PM

Quote:

Plus, any self respecting geek should have at minimum 3 unused power supplies around the house

[/B]

amen.

jrhupp · #18 10/17/2006, 04:29 PM

I have heard there are issues associated with using a computer power supply longterm with only 12V devices, as they are primarly design for a 5V output. It was suggested in the source I used to put my power supply together that a load be connected on the 5V output. In my case I used a large 1/2 watt 100 ohm resistor. I don't remeber exactly what the reason was, nor do I have the link (so I guess it is not much help). But I do rember that my instructions came from an RC-hobbiest forum, where they were using them as trickle chargers and bench top power supplies.

Jay

corivus · #19 10/17/2006, 05:06 PM

hah, I was going to try this last night and my g/f yelled at me when I started taking apart the power supply and rewiring stuff hehe

Altpers0na-old · #20 10/17/2006, 06:20 PM

I have not done extensive testing on the subject, but i see no reason to put a load on a line you dont plan on using.

the transformer plug from curtisk's post is a very good option as long as the current rating is ok. the pc power supply goes much higher than a plug-in like those will go.

i would not use a paper clip or wire to jumper the thing into running. it would work, but i hate being electrocuted. even just a bit.

there is a decent article on hackaday.com about turning your pc power supply into a bench top power supply,

hmpit_ags2006 · #21 10/17/2006, 06:27 PM

Could I just splice the green wire to a ground? I tried a paperclip and it worked for about 10 seconds and then it stopped.

hmpit_ags2006 · #22 10/17/2006, 06:33 PM

Altpers0na,
Do you know where that article is? I looked for it and couldn't find it.

hmpit_ags2006 · #23 10/18/2006, 10:02 PM

bump

Donw · #24 10/18/2006, 10:15 PM

Jumper the black to the green. Yellow is + blk is -. Beware this mod creates electrical line noise and may make your tv go fuzzy and no x10will work with the supply on.

Don