[TomW16]

I purchased a no name computer power supply from NewEgg for $15 to power a computer fan.  I hooked up the fan to the power supply but it didn't work.  I used my volt meter to verify voltages and I only get 5V off of a purple line and a green line.  All other voltages are dead.  The 5V powers the fan at the lowest setting so I know the fan works.

Do I have a defective power supply or does the connector need to be attached to something to get 12 volts?  I am not a computer guy so I am wondering if I am missing something obvious.  If not, (and I don't think I am) I need to exchange the power supply.

For those curioius as to what I am doing, I am building a box to house my modem, router and NAS (which will eventually house my music collection via squeeze center) and the fan is to provide air movement through a filter since the box will be located in my workshop that can get dusty from woodworking.  A $15 power supply was easier and less expensive than trying to make one with connectors.

Thanks in advance.

Tom

[shokunin]

I'm assuming this is an ATX power supply.  What you're voltmeter is telling you is that the 5V standby power is active.  All other lines are off until you power up the ATX supply, this is not the same as turning on the power supply switch.  You need to jump two pins using an adapter like this:
http://www.performance-pcs.com/catalog/index.php?main_page=product_info&cPath=101&products_id=2850

or switched one..
http://www.performance-pcs.com/catalog/index.php?main_page=product_info&cPath=101&products_id=3163

This will then turn on the ATX power supply and all the other lines will be live

[TomW16]

So there is a bit more to this than meets the eye.   Thanks shokuin; you're a life saver as I was all set to return the power supply!  Rather than ship a $1.95 part that appears to only act as a jumper, would you happen to know the two pins that need to be jumped to power up the power supply?

Thanks again.

Tom

[TomW16]

After a little Googling, it seems that I can wire up a switch from the green to the ground (black) and everything should power up.  I'll give it a shot and report back.

[TomW16]

Thanks again shokunin.  I jumped the green wire to ground and it worked perfectly.  You just saved me some embarassment and $8 in return shipping charges.

Have a wonderful evening.  You just made my weekend!

Take care,
Tom

[shokunin]

Tom,

Glad it worked, I too have a squeezebox actually the boombox in my woodshop err. garage. 

Glenn

[Levi]

You went all that trouble.  You could have bought a power supply from Radio Shack.  They also have other power supply with variable voltage settings so you can control the speed of the fan.

[TomW16]

I looked at stand alone power transformers like the one from Radio Shack (although I didn't look at that one specifically) and they were all over $15.  I figured that the computer ATX power supply had the necessary connections to power the computer fan without splicing wires so the ATX power supply seemed to make the most sense. 

Unfortunately my lack of computer knowledge resulted in what I thought was a defective power supply.  Once I was informed about "turning on" the power supply with a jumper wire (thanks again Glenn), it worked perfectly. 

I am using a variable speed computer fan with a remote knob so that I can adjust and set the fan speed manually.  The fan (110 max CFM with ball bearings) was $16 and cost more than the power supply  .

I am very greatful for the knowledge offered in these forums.  I don't know how people got by without the internet.

Thanks.

Tom