Go out to eBay and find this PDB:  Supermicro PDB-PT825-36824 SC825.  It features three GPU power cables.  Each GPU cable has a one 8-pin and one 6+2 pin connector.

After this PDB arrives, strip off the metal plate.  You won't need it.

The Supermicro PDB-PT825-36824 is a "23-pin" model and will accept both the 23-pin supplies and the 19-pin supplies.  This is not an exhaustive list, but just the various models that I had sitting at home that I know fit into the PDB-PT825-36824.

23-Pin Model Numbers

• PWS-1K28P-SQ | Quiet, 1000W at 120V, 80 Plus Platinum
• PWS-920P-SQ | Quiet, 920W, 80 Plus Platinum
• PWS-1K41P-1R | Loud, 1100W at 120V, 80 Plus Gold

19-Pin Model Numbers

• PWS-1K21P-1R | Loud, 1000W at 120V, 80 Plus Gold

If you choose to find a model that is not listed above, you should start by looking at the Supermicro Power Supply Matrix.  The only supplies that will physically fit have these dimensions:

• Length (mm) = 336
• Width (mm) = 76
• Height (mm) = 40

Unfortunately, the matrix doesn't tell you which supply is 19-pin and which is 23-pin.  However, if you do a Google search like this:

"PWS-1K28P-SQ" site:supermicro.com

 Then you will get as your top hit this link:  https://store.supermicro.com/1280w-1u-pws-1k28p-sq.html

Scroll down to the 'Detailed Specification' tab, then look for "Output Type    Gold Finger (23 Pair Connector)".

I am using two PWS-1K28P-SQ supplies:

If you look at Step #1, you will notice how the 24-pin and dual EPS12V cables are extremely short.  If your motherboard has its 24-pin connector at the top of the board, you will need a 50 cm extension.  If your motherboard has its 24-pin connector on the side, a 30 cm cable will work.

I purchased a 50 cm extension kit because my ASUS Pro WS x570-ACE motherboard has a single EPS12v connector on top.

My cable extension kit:  Amazon - LINKUP

The standard 2U Supermicro server case has rather good airflow, which keeps everything chill.  Because we have stripped all that away, there is no telling if the PDB will receive enough airflow to stay cool.  To address this potential issue, I chose to include a 40mm fan, blowing across between the PDB layers.  When you order a fan, make sure it has a 3 or 4-pin rectangular connector, so it plays well with standard ATX motherboard fan headers.  I highly recommend you use a top quality fan because if this fan goes bad, you have to do a lot of work to replace it.

You really can't go wrong with this:  Noctua NF-A4x10 FLX, Premium Quiet Fan, 3-Pin (40x10mm, Brown)

The soldering iron is used to heat the brass knurled inserts into the printed model.  My iron is a Hakko FX-888.  Total power is 70W, and works great for heating the brass inserts when set to 730 F / 390 C.

A standard soldering iron tip isn't made to press a brass insert down into a 3D model.  Therefore, I recommend a set of these heat-set inserts:

Heat-Set Insert Installation tip for Hakko FX-888D #4-40, M2, M2.5, M3, M4, and M5 Inserts

These bad boys have so many different names that a single eBay/Amazon search won't find all the sales.  Here is a list of adjectives that you should use when searching.

• Knurled
• Insert Nuts
• Blind
• Blind Hole
• Single Pass Through
• Brass
• Injection Molding
• Threaded

Here are some photos of what you are looking for:

I highly recommend that you look for the inserts that are labeled "blind".  These nuts are closed at one end; see the middle photo above.  I believe the blind nuts are superior to the open-ended nuts because when you press a hot brass nut down into the filament, it melts and scrapes the walls.  This melted filament has the potential to build up at the bottom of the nut and ooze its way up into the threaded area.  Effectively, this can reduce the total length of internal threads that a screw/bolt can grab on to.  Blind nuts do not suffer from this problem.  Unfortunately, M2.5 blind nuts can be difficult to find.

This is the droid size you are looking for:

• M2.5x3.8x8mm blind
  
• M2.5x3.8x8mm non-blind

This is a long list, with some very small counts.  You might be able to find some of the M2.5 and M3 bolts as a combination pack.

Hex Socket Cap Bolts, Nuts, and Washers:

Hex "Ultra Thin Low Flat Wafer Head" Bolts:

This PSU adapter is so long that I had to break it into three individual parts:

1. The "AC Cable Third"
2. The "Middle Third"
3. The "PDB Third"

Known for my creative naming skills, I am not.  These names are how I refer to the 3D prints throughout this instruction set. 

Open your slicing program.  Orient the pieces as shown.  Infill at 100% for a good solid print.  Use a minimum of 5 perimeters.  Zero supports.  I also recommend you use a seam position of "Nearest".

Ok, so I lied when I said nothing in this project needs supports.  This next image is of the PDB Circuit Mount.  When you lay it on this side, supports are only needed in the two small slits.  Also, I highly suggest you stick with 5 perimeters and don't drop below 25% infill.

When printed, they should look like this: