Dual PSU Adapter Mod - The Proper way to run Multiple Power Supply's

**Zaid** · 17th July 2011, 10:37 PM

Good evening fellow members, It’s been quite a few months since I wrote anything with the slightest relevance to modding and I know a lot of you out there had many unanswered questions regarding my most recent case mod “G.H.O.S.T”, my 3 ~ 4 year old HTPC that I re built into a dedicated system for gaming. I understand what intrigued most of you, if anything, was its classic simplicity and the fact that the system ran on 2 power supply’s. In the coming weeks and months I will perform a number of mods, but for now let me show you the proper way to make yourself a dual psu adapter.

Now there might be a lot of reasons why you would want to use 2 PSU’s, it could be you want to use a Quad SLI system, maybe use 4x GTX480’s? There isn’t a certified PSU in the market that can deliver that much power on a single 12V rail, even using one of those 1600W PSU’s would be pushing it. Specially when most House grids can only deliver around 1600W-2200W’s. Or maybe you already have a few good PSU’s at home, and would like to put them to use.

I remember showing you all the basic principal of the Dual PSU mod quite a few years ago, since then I haven’t really been able to write more about this subject or show you how; even though I said I would. However, Consider; like many of my mods, This will NOT void your PSU’s warranty, We are making an adapter that will run both PSU’s simultaneously. We are not cutting into or modifying the PSU’s themselves. Nevertheless, let us get on with it, shall we..

Parts Required

A
2x 20/24 Pin Female ATX Connector
1x 20/24 Pin Male ATX connector
Some Heat shrink / electrical insulation tape and a few meters of electrical wiring

Or B (The Preferred way)
2x 20/24 Pin Male to Female PSU ATX Connector Extending Cable
Some Heat shrink / electrical insulation tape and a few meters of electrical wiring

Or C

1x 20/24 Pin Male to Female PSU ATX Connector Extending Cable
Some Heat shrink / electrical insulation tape and a few meters of electrical wiring

Tip:
If you wanted to skip on the adapter to save yourself a few bucks here and there and don’t mind cutting into your PSU’s ATX connector wire to install the female extension, you could do that too. However I found it most easy if you would just buy two 20/24 Pin Male to Female PSU ATX Connector Extending Cable’s from any computer hardware shop and simply go from there. Just remember to get quality material.

Now the basic principle is still the same as I outlined it so many years ago, and yet it’s somewhat different. The idea is to have both PSU’s simultaneously and automatically start and shutdown at the same time, eg. When you press the start button, or when you shutdown the computer. This can either be achieved using an external relay that tells the slave PSU when to start and shutdown; Or we could reverse that by using the one already present in your motherboard by making a connection between the Green Pin (#14) and Black Pin(#16 or any other Ground)

As you can see from the diagram you are to basically make two connections, one between the Green (Pin #14) and the other between Black (Pin #16 or any other Ground pin).

Directions
You need to cut two pieces of electric wire, lengthwise they should be just about long enough to reach your second PSU and maybe have a couple inches spare. I took a meter (3.5 feet). Now take one of the 20/24 Pin ATX Extending Connector and carefully strip off a few mm of PVC insulation from Pins #14 and #16, just enough so that you can solider and join the two separate pieces of wire’s you cut out earlier. Make sure a good connection is made and then insulate it.

Now take the other ATX Connector Extending Cable and cut off the female 20/24 Pin ATX Connector, then strip off every other wire expect for the ones leading to Pin’s #14 and #16 (Green and Black one ). After that’s done and cleaned up, you should take the two extended wires and respectably solider join them to Pin #14(Green) and Pin #16(Black) wire coming out of your new Female Connector. Remember not to Mix up the Pin’s & wires, Green goes to Green, Ground to Ground.

And don’t forget to slide in some heatshrink before you make the solider joints, using heatshrink is preferred but you could use electrical insulation tape over them later on so they don’t short out.

Your final Product should look something like this

Sorry I couldn’t provide more in-depth pictures as I didn’t take any during the adapter’s construction but I’m sure this guide will give you a pretty good idea how it should be built.

NOTE: Now that you know how to make the adapter, also know this. I only recommend using a higher – midrange PSU that fully supports “NO LOAD OPERATION”; Meaning even if you just load certain rails on the PSU, it’s less likely to fail and will continue to work properly. Avoid using cheap lower end or generic PSU’s for a Dual PSU setup, if you use a cheap PSU then most likely your second PSU will die, you also risk damaging other devices in your computer.

So, please be a little careful when you do this mod and if you are unsure, have any doubts or questions in mind just ask and I’ll try to help you out with it.

Well, that’s all the modding for today, till next time when we meet, take care and happy modding

Cheers,
Zaid H.