Compaq DeskPro EN Power Supply

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I have a DeskPro EN MOBO with a 24 pin power connector. This is not wired as
a standard ATX.  Does anyone have the pin-out information so I can rewire a
standard ATX?
Thank you.

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Re: Compaq DeskPro EN Power Supply

On Fri, 27 Apr 2007 21:06:17 -1000, "John Keiser"

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Check the original PSU label, the board may require 3VSB
power which is not available on an ATX PSU.

There are multiple boards that might be in something called
a "DeskPro EN", or not?  I suspect not enough info provided
to be certain enough to rewire one although if you have a
multimeter you can check a few things, like on the
motherboard power socket, positions like 5V or 3.3V (not
3VSB nor 3.3V AUX) would have continuity between them.  This
assumes you don't have the original supply to compare
against.  If you did have it I would wonder why not use it?
It might be easier to just fix a fault in one than to
require an ATX.  Easier being relative, fault finding and
ability to source parts is a factor, while anyone with
reasonable soldering skills could just graft wires.

The following link is to a pinout I'd posted a few years
ago, I'm not entirely sure but I have a PSU part number it
"might've" came from - 243890-001, Compaq Spare 244166-001,
though another part # on the label is 246444-003 and Series
PDP116P, Model PS-7231-6CF.  There are 3 bar codes too with
different numbers, a "Rev 05 C0145" sticker.

It's almost amazing how many part numbers this thing has on
it's label, all to describe itself, not any systems it might
go into.  It might be easiest to just take some part numbers
and search for a surplus stock of compatible PSU somewhere.
I don't know if the one I had and the part numbers listed
above are what you need or not, that unit had a different
form factor that was a little narrower but taller, used a
92mm fan in back instead of 80mm. &

Here is an excerpt from above linked post-

Pin #     STD ATX 12V        Compaq 24-pin

<1>       +3.3 VDC            +3.3 VDC            Brown
<2>       +3.3 VDC            +3.3 VDC            Brown
<3>        COM                 COM
<4>       +5VDC               +5 VDC              Red
<5>        COM                 COM
<6>       +5 VDC              +5 VDC              Red
<7>        Com                 Aux Gnd (from aux board)
<8>        PWR ok              N/C
<9>       +5V SB                   +5 (from aux board)
<10>      +12 VDC             +12 VDC             Orange
<11.1>    +3.3 VDC            +3.3 (from aux board)
<11.2>     3.3V sense
<12>      -12 VDC              Fan CMD            White w/
Red Stripe
<13>       COM                +3.3 VDC            Brown
<14>       PS - On            +5 VCD -12V?        Blue
<15>       COM                 COM
<16>       COM                 Power On   White  (ONSTBY)
<17>       COM                 COM
<18>      -5V                  COM        Black (2nd wire,
black RTNRS)
<19>      +5 VDC               COM
<20>      +5 VDC              +3.3 VDC            Brown
<21>      ------              +5 VDC              Red    
<22>      ------              +5 VDC              Red
<23>      ------              +3.3 VDC Sense      Brown
<24>      ------               Fan_sink   White w/ Blue

HOWEVER, I vaguely recall that even using a seperate supply
with common ground to supply 3V power in lieu of 3VSB/Aux,
plus a pin-adapted standard ATX PSU, it was not enough to
turn on a certain Compaq system but I don't recall the model
# or name of that system anymore.  If I'd been on-site I
might have been able to resolve the incompatibility but
remotely all I could do was dissect the original PSU to
arrive at the pinout.

Re: Compaq DeskPro EN Power Supply

The original PSU was tossed so I am just taking a shot at reviving what
should be a useful PC.

I was unaware of the "3VSB/Aux" issue and assumed that 3.3 would suffice.

I have several spare ATX PSUs and may try anyway with pinouts you gave.

Thank you for an extremely good answer.

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