I got a new Dell brick. Also, independent tests revealed that PW-200 might not work for my motherboard. So I swapped it for a PicoPSU-150-XT. Then I did the mating with standard extension cables as follows.
A 20-pin ATX male socket has two regions where a Dell DA-2 can be plugged in. These are marked in the diagram on this powerstream web page
. So, one can in principle plug two Dell DA-2s into the socket to achieve a total of 400W power. In the following, I am dealing with only one. You can find the P4 connector's pin-out on this playtool page
I started from the 24-pin ATX extension cable and removed all the pins from the male socket.
Call the two P4 extension cables P4-A
. I removed the male sockets on both of them, leaving the wires with only male pins attached at one end and connected to a female connector at the other end.
- I inserted P4-B
wires into the ATX male socket, yellow wires at positions that correspond to Dell's pins 3-4, and black wires at positions corresponding to Dell's pins 7-8.
- I inserted P4-A
wires to the ATX male socket at positions corresponding to Dell's 1-2 & 5-6, but with a few modifications. I removed the yellow wire at pin 1 entirely. (This would have gone to the 'reserve' line of Dell.) I removed the black wire at position 3 from the female end of the P4-A
, even though I inserted the male pin into the ATX male socket. (This is getting connected to the 'remote' line of Dell.) To keep my colors clear, I actually replaced the black wire by a red wire from the ATX extension cable.
- I plugged in the P4-B
's female plug into the PicoPSU's power input socket. The P4-A
's female plug went into the motherboard's P4 socket. (Note that two circuits from Dell DA-2 are going into the Pico, providing a nominal 144W power, and one cirtuit is going into the motherboard/CPU, for a nominal 72W power.
Now, plug in the Dell DA-2 into the ATX socket and we are ready to go, except that the power brick is still on standy. We have to ground the 'remote' wire which is currently hanging. Where are we going to find a ground line? Remember that the PicoPSU has its own P4 connector, which we are not using. I shorted the 'remote' wire to the Pico's P4 ground line using a paper clip. The brick turned on and I tested to see if everything worked.
The paper clip is not a permanent solution of course. If one is willing to do some soldering, the 'remote' wire can be soldered to any ground line available. But is there a way to ground the 'remote' wire without soldering or crimping? Well, there is. Find an idle 20-pin ATX female plug. If you purchased an ATX extension cable for the male socket, then you have one lying around. Insert the 'remote' wire (currently terminated by a female ATX pin) into the position 14 and a ground wire into the position 15. (If it is a 24-pin plug, then adjust the position numbers accordingly.) Then plug this into the ATX PSU bridging tool. Voila!
I will post some pictures when I get a chance.