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Need help wiring old AT psu to ATX psu

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Dec 20, 2000
I found serveral guides on hooking up 2 ATX psu together via a relay so that they will turn on together. But I want to use my AT psu to power my fans and I do not know what is the correct type of relay to use. Radioshack sold me one that has only 4 terminals. The problem is that my AT psu switch has 4 wires (blue, brown, white and black), I've tried different 2 wire combinations, none of them work; the other 2 terminals are hooked up to the 12v + ground of my ATX psu.

Anyway, I got my hands on a Jameco catalog now but I am overwhelmed by the choices in there. What type of relay shd I look out for?

So far, I can figure only figure out 1 thing :
Coil Voltage : 12VDC
Style : SPST, DPDT, 4PDT??
Contact Voltage : ?
Contact Current : ?
No of terminals : ? (minimum 6?)

One more thing, most guides say that I need a 1amp load on the 5v line or else the 12v line will not put out 12v. Any idea on what I can put on the 5V line that is 1amp? A resistor perhaps?

Any help will be appraciated.

Thanks Da Whip, but that's for hooking up 2 ATX psu. I need a how-to for ATX + AT.
the AT psu will have 2 leads to the switch that gives the "power good" signal and turn on the supply. Using the relay system, you could just substitute the ATX leads for the AT ones right?
My AT psu has 4 leads going to the switch. I tried using just 2 of them but no go.