John said:
It's a mystery
And every time I read about a user in this situation, I
can hear some engineers snickering in Taiwan. Must be a
big joke to sell undocumented products.
There are standards for power supplies, but the standards
do not prevent the designers from being creative if they
wish. And the supply could have three separate outputs,
or it could have one output driving all three "faked" 12V labels.
One indicator of a common output, is when the current rating
on all three rails, is exactly the same. But that is not so
in this case.
There are some pictures here, and maybe you can figure it
out from the pictures:
http://www.bigbruin.com/2006/coolmax600_3
Review comments here as well:
http://www.newegg.com/Product/CustratingReview.asp?item=N82E16817159057
Did the unit come with a manual ? One of the higher
output Coolmax units comes with a manual of some sort.
(This picture is from an 850W Coolmax manual. But they
don't have to be made the same way, and this is a quad
output unit anyway.)
http://www.jonnyguru.com/PSU/CTG-850/IMG_0780.jpg
As for methods, you could use an ohmmeter, and see which
pins are joined to which other pins (with the unit completely
unplugged from everything). A second method is
to fire up the power supply with no motherboard connected.
It would be nice to connect a load to the 3.3V or the 5V
rail, but ideally with nothing on the 12V. The purpose of
doing that, is so the three 12V rails can establish their
own voltage level. Like a "signature", each unique rail should
be a slightly different voltage. If all 12V wires, while
unloaded, give exactly the same voltage, then you know there
is only one rail driving it. That is as close as I can come to
figuring out wiring, without opening up the unit and looking
inside.
Good luck,
Paul
