Weird dual PS behavior.

[acrh2]

I'm having some weird dual PS behavior in a new system I am building.
I've pretty much combed the entire internet for dual PS setup info and I still couldn't find the answer. Multiple guides state that shorting green wire pin (pin 14, PSON) and any black pin (GND) would start an ATX PS. Or that it wouldn't, depending on a particular PS.

In my case, it doesn't do either. The PS in question is Antec Truepower 430, and at the moment, I only have 2 Coolermaster Aerogate III fan controllers and 6x120mm fans connected (to be added are 4 harddrives and 2 cd/dvd drives, and a watercooling setup in the future). When shorting those two wires, the fans turn on for an instant, and stop. However, if I quickly short twice in succession, the PS starts and stays on.
Has anyone experienced anything like this before?
Will using a dual PS cable from a CM Stacker work to start this PS?
In a related issue, I am also considering a custom mod where the two PS units would have connected together green wires, and separately, black wires. Does anyone know from where such a modded cable/setup can be purchased?

 

[Ice Czar]

first link
while you nailed the Power On signal you missed the power good signal (grey to black on the second PSU)
and the reason a single ATX PSU may or maynot turn on with just the the Power On is the load it needs to detect, adding a few drives is generally enough load to have any ATX turn on.


cut and paste 101
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synch 2 PSU each as a seperate bus

1. Hardwired (what a CMStacker's adapter does)
2. With a relay

or employing a shared bus Like a redundant PSU

1. with resistors
2. with mosfets
3. with diodes (Single Source Fault Tolerant Power Systems)

(3 is slightly outdated now see gee's post > http://hardforum.com/showthread.php?t=776885)

I ran 2 hardwired 400 watts and a large RAID array for 3 years without issue on one of my boards (Abit KR7A)
however it may have been a contributing factor in the death of another board (ECS whatever )
though Im not at all sure about that

not running them synchd however certainly corrupted the hell out of the array
eventually switched to a Zippy Emacs MR3-6450P N+1
with considerably less total wattage but plenty for what was actually required
with 32A on the +12V rail for the drives and considering the mobo's VRM was powered off the +5V
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[acrh2]

I'm no electrical engineer but I believe that I have it figured out after reading the ATX specs from www.formfactors.org.
"Power Good" pin has nothing to do with the power supply being on. It sends a signal to the motherboard to let it know that a good and stable power coniditions are reached at the power supply so that the motherboard can operate normally. Shorting that pin with ground would accomplish nothing.
"Power On" pin is used by the motherboard to send a signal to the PS that it needs to be on. The signal is a low TTL with the voltage < 0.8V. Anything higher or an open circuit means that the power supply should turn off. In principle, according to the ATX specs as I understand them, shorting ground and PSON pins should accomplish nothing. I imagine that it's up to the PS manufacturer to make it work or not, and that's why it doesn't always work.
The only reliable way to use a second PS is to have it connected to the correcponding PSON pin in the motherboard, parallel to the first PS. I imagine that motherboard generates a constant ttyl low from the +5VSB line, and whenever you need turn power on, you just short it to the PSON pin by hitting the power button.

Well, it's all in the specifications, go read them.