How do I turn-on an ATX Power Supply?

[21stHermit]

I'm building a JBOD hard drive array using an old computer case and its ATX power supply. I need the 5V and 12V 4-pin molex connectors, nothing else. I will not be using the MB or CPU, just USB to IDE/SATA adapters and a USB hub.

Since there is a "soft switch" on the case which connects to two pins on the MB, I figure there's a relay on the MB or in the PS to "turn-on" the PS. In any event, the PS gets instructions from the OS to stay on or shut down.

I assume I can short two pins on the PS to MB connector to keep the PS on, then use the rear switch on the PS to turn things on and off. IIRC, that's how the older AT PS's worked. Can anyone guide me as to what I need to do?

Also, is there a connector I can use for a case fan(s) or do I need to splice into one of the PS leads for a fan?

Many Thanks
Hermit

 

[John]

Use a paperclip (or other wire) to jumper the green & a black wire.

 

[dBTelos]

http://www.hardwaremods.com/guides/psu_jump/psu_jumping.html

 

[21stHermit]

Thanks John,

Originally posted by: John
Use a paperclip (or other wire) to jumper the green & a black wire.

Worked as you suggested.

Hermit