[PLUG] Is this info accurate? I need to...

Darkhorse plug_0 at robinson-west.com
Sat Oct 2 17:06:02 UTC 2004


modify an ATX 400W power supply designed for an AMD K7
or Intel P4.  As the guy below says, there's no power 
switch built into an Enorex Microsystems PC164 
motherboard.  Why Enorex didn't include a circuit 
so that commodity ATX power supplies will work 
with their motherboard is beyond me.  

     --  Michael Robinson  



As far as I know there is not a motherboard connection for the power-on
function in the power supply (went down this same road <grin> and had to
reverse engineer the ATX power supply to figure out what was going
on...)...

If you check the power supply wiring definitions (use an ATX Intel based
motherboard for the pin defs) you will find one of the connector pins
(fourth over from the only 3.3V pin on one side I think) labeled
something
like DC_CTL or such - anyway, it is usually a rather thin green wire in
most
ATX power supply wiring to the motherboard - this is the DC power
control
line and when tied to ground will "turn" on the DC output of the power
supply (that is the method the ATX motherboards use to control the DC
power
to the system for power down operation). If you take the wire and tie it
to
ground you can use the power switch on the back of the computer case to
control the power (and it had the advantage where you or someone else
can
not accidentally power down the system from the front "pwr" switch
<grin>)...

Once you make your changes check the power supply outputs PRIOR to
connecting to the motherboard to make sure you have everything wired
correctly - nothing worse than letting the "magic smoke" out of the
motherboard because of a wiring mistake!!!

hope the information helps...

gm.. 










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