Layout Power supply Deskpro EN

[Bruno Keller]

x-no-archive: yes

Hi all,
i have a Compaq "Deskpro EN" Small Form Factor where the power supply does
not work anymore. I like to use a standard ATX power supply for replace. But
the Compaq power supply does only have 14 Pins instead of 20 like the ATX.
Does anyone have the layout of the compaq power supply and can tell me, if
it is possible to use a regular ATX ? Maybe i have to cut some pins - but
which ones ;-)

The ATX layout i have:
Pin # STD ATX 12V

<1> +3.3 VDC
<2> +3.3 VDC
<3> COM
<4> +5VDC
<5> COM
<6> +5 VDC
<7> Com
<8> PWR ok
<9> +5V SB
<10> +12 VDC
---------------------------------------------------------------
<11.1> +3.3 VDC
<11.2> 3.3V sense
<12> -12 VDC
<13> COM
<14> PS - On
<15> COM
<16> COM
<17> COM
<18> -5V
<19> +5 VDC
<20> +5 VDC

Thanks
Bruno

 

[kony]

x-no-archive: yes

Hi all,
i have a Compaq "Deskpro EN" Small Form Factor where the power supply does
not work anymore. I like to use a standard ATX power supply for replace. But
the Compaq power supply does only have 14 Pins instead of 20 like the ATX.
Does anyone have the layout of the compaq power supply and can tell me, if
it is possible to use a regular ATX ? Maybe i have to cut some pins - but
which ones ;-)

I don't understand why you would choose to not have this post
archived... it's exactly the kind of info that would be useful to
someone in the future, unlike many of the frivolous conversations that
take place on usenet.

Anyway, you need to take a look at your dead power supply, note the
wiring color and positions. At a minimum it supports 5V and 12V.
Note the colors of those wires to the drive connectors... It's also
very likely the ground is still black, but note that as well.

Next match up the colors on the motherboard power connector... there's
only a few things they may've likey done to reduce the pin count...
either doing away with -5V, -12V, and a single 5V, 12V, and couple
ground wires, or more likely, it doesn't use 3V power.

It is most likely that it doesn't use 3V power, that it's essentially
an AT power supply with an ATX-like connector. Check the chassis to
determine whether it uses an AC power switch to the front bezel for
power on/off, or not. The AC power switch is fairly obvious, it's
much larger, has a thick electrical cord instead of small high-gauge
wires.

 

[CBFalconer]

I don't understand why you would choose to not have this post
archived... it's exactly the kind of info that would be useful to
someone in the future, unlike many of the frivolous conversations
that take place on usenet.

I agree. In fact, my attitude to such an antisocial header is not
to bother supplying any information I may have. Unfortunately too
many newsreaders allow it to be included in the headers, and thus
hide it on the newsgroups.

 

[Bruno Keller]

I agree. In fact, my attitude to such an antisocial header is not

to bother supplying any information I may have. Unfortunately too

sorry folks - i agree to. I didn't remark it as it was a "default" template
where i'm using for posts in groups where the threads are not really
important to keep them and fill up the usenet ;-)

Bruno

 

[Bruno Keller]

Thanks Kony
i found the wiring of the 14-pin supply

Compaq Supply | Standard ATX

1 +3.3Vdc | 1 +3.3Vdc
2 +3.3V Sense | 2 +3.3Vdc
3 Signal GND | 3 Signal GND
4 +5Vdc | 4 +5Vdc
5 Signal GND | 5 Signal GND
6 +5Vdc | 6 +5Vdc
7 Signal GND | 7 Signal GND
8 +3.3Vdc | 8 PWR-OK
9 -12Vdc | 9 +5VSB
10 Fan Off | 10 +12Vdc
11 On/STBY | 11 +3.3Vdc / 3.3V Sense
12 +5V Aux | 12 -12Vdc
13 +3.3V Sense | 13 Signal GND
14 +12Vdc | 14 PS-ON
15 Signal GND
16 Signal GND
17 Signal GND
18 -5Vdc
19 +5Vdc
20 +5Vdc

So, as i can see the pin 9 - 14 are different. How to connect ?
ATX 12 to Cpq 14 ?
ATX 11 to Cpq 13 ?
ATX 19 to Cpq 12 ?
ATX 14 to Cpq 11 ?
ATX ?? to Cpq 10 ?
ATX ?? to Cpq 9 ?

thanks

Bruno

 

[kony]

Thanks Kony
i found the wiring of the 14-pin supply

Compaq Supply | Standard ATX

1 +3.3Vdc | 1 +3.3Vdc
2 +3.3V Sense | 2 +3.3Vdc
3 Signal GND | 3 Signal GND
4 +5Vdc | 4 +5Vdc
5 Signal GND | 5 Signal GND
6 +5Vdc | 6 +5Vdc
7 Signal GND | 7 Signal GND
8 +3.3Vdc | 8 PWR-OK
9 -12Vdc | 9 +5VSB
10 Fan Off | 10 +12Vdc
11 On/STBY | 11 +3.3Vdc / 3.3V Sense
12 +5V Aux | 12 -12Vdc
13 +3.3V Sense | 13 Signal GND
14 +12Vdc | 14 PS-ON
15 Signal GND
16 Signal GND
17 Signal GND
18 -5Vdc
19 +5Vdc
20 +5Vdc

So, as i can see the pin 9 - 14 are different. How to connect ?
ATX 12 to Cpq 14 ?

No, that's -12V.
ATX 10 to Cpq 14

ATX 11 to Cpq 13 ?

Seems good.

ATX 19 to Cpq 12 ?

No, a standard ATX has more 5V leads than needed, you'll have to clip
them off, desolder at PCB, whichever, but they wouldn't be
connected... same goes for the unused GND (ground) leads. 5V Aux is
"most likely" the always-on power to the motherboard, equivalent of
the +5VSB on a standard ATX.

ATX 9 to Cpq 12

ATX 14 to Cpq 11 ?

Maybe? It might be that simple, but might not. The last proprietar
Compaq supply I saw, had more than 14 pins, but wouldn't turn on when
a standard ATX PS-On signal was substituted for the "On/STBY". It
would've helped if I had the Compaq motherboard when I did that
testing, since all I know for sure is that they did "something" odd...
ATX 14 to Cpq 11 is the first thing I'd try though, failing any futher
info.

ATX ?? to Cpq 10 ?

Cpq 10 would go used, as far as I know.

ATX ?? to Cpq 9 ?

ATX12 to Cpq 9


I can't guarantee that I'm right though, Compaq seems to go to extra
efforts to thwart compatibility.

 

[Bruno Keller]

thanks again.

just saw that Pin 8 is also different.so i guess i do not have any 3.3 V. What happen when i take +5 (ATX 19 or
20)

No, that's -12V.

ups... yes, thanks

a standard ATX PS-On signal was substituted for the "On/STBY". It

is this eventually Pin 8 from the ATX ?

I can't guarantee that I'm right though, Compaq seems to go to extra
efforts to thwart compatibility.

yep, and a reason to take 160$ for a new power supply ! (Price in
switzerland).

so, i try:
ATX 10 to Cpq 14
ATX 11 to Cpq 13
ATX 9 to Cpq 12
ATX 14 to Cpq 11
Cpq 10 is not used ? btw: on the dead ps the color is purple (violet)
ATX12 to Cpq 9

ATX?? to Cpq 8


Bruno

 

[kony]

thanks again.

just saw that Pin 8 is also different.
so i guess i do not have any 3.3 V. What happen when i take +5 (ATX 19 or
20)

you're right, the ATX 8 should not be connected to Cpq 8.
The ATX power supply has more 5V leads than the Compaq, so ATX19 and
20 may go unused, as i mentioned previously.

ups... yes, thanks

is this eventually Pin 8 from the ATX ?

No, Cpq 11 to ATX 14. There is nowhere to connect ATX 8, it would
also be unused.

Again, I don't know if the replacement will work like this. It might
be a good time to consider upgrading the motherboard, so you have a
standard motherboard supporting a faster CPU, which will accept the
standard ATX power supply.

 

[Bruno Keller]

Tried it, on sereval ways.. no luck. No power.
Bruno