Dell PE T420 Non-redundant to Redundant Power Supply conversion

FYI, for anyone looking to do this, given that this is old hardware at this point, i don't see the harm.  Obviously this is not supported by Dell. I just completed the upgrade going from a single non-redundant 500-ish watt PSU to dual 750 redundant PSUs.  This is going to be our 'production lab box'.  I can run a dozen VMs on this box quite easily.

The upgrade is actually quite simple if you've been inside a computer before.  Parts list:

2 redundant PSUs - easy to find on ebay or Amazon for less than $50 each. Several options.  Just google T420 PSU upgrade. i personally used dual 750w.   some part number examples for the 750w: 5NF18 79RDR 6W2PW
K501P  - power supply backplane $25 ebay
KKY3X -  power distribution board - $70 ebay (or less)
COF3T - divider (separates the two supplies)  $200...but not really necessary.
2-3 motherboard screws

I bought my setup in an ebay kit that came with the divider.  Interestingly the sheet metal divider piece COF3T is the hardest part to find and you literally cannot find it anywhere for under $200 purchased alone.  You can almost get a full used chassis for that amount.  Anyway, this piece seriously seems completely optional/superflous to me.  You just need to use a SLIGHT amount of care when inserting the supplies...and even if you are ham-fisted, it'd be hard to  something up.  If I were to do this again for a lab box, I'd get two of the 750s on amazon for $30 each, a used backplane for $25 on ebay, and a distribution board on ebay for about $70 and be done...for around $150....and skip the divider thing.

Installation is a HAIR tedious, but again, nothing much if you've ever been inside a computer before.  

All you do is remove the old supply (loosen cable management clips and unplug all connectors paying careful attention to where they went, loosen 1 screw, slide it out.)

Put the backplane in place on the bracket.

Move the remaining cabling out of the way to make space to drop in the PDB.  position it and slide it into the backplane socket. secure the PDB with 2-4 motherboard screws.

replug the connectors from the PDU to the motherboard and disk backplane.

slide in your new PSUs.  

fire that baby up.

it's always a good idea with PE servers to go into the lifecycle manager and tell it to inventory the new parts when you change something out.  in my case, idrac picked up the change immediately and it didn't seem necessary but i think that's a good habit anyway.

Thank you so much for posting this. I have a T420 whose power supply just failed today (no green light when plugged in), and have been searching for economical replacements. The possibility of replacing the single 550W with dual supplies is such welcome news! I have two followup questions:

1. Does the new redundant power supply scheme have the same outputs, for example for a DVD drive and other components of a T420, or is there a difference?
2. Do you by any chance know where to find a diagram or photo of the placement of the new boards in the chassis? Never mind – Googling and looking through images finally netted a photo of the inside of a chassis with dual PSUs and now it's more obvious what has to happen.

Thank you again!

To anyone interested: Dell has useful videos about the T420, including the power distribution board and power supply backplane, at https://qrl.dell.com/Product/Detail/15

I recently had a PSU failure in my T420 and this thread has been very helpful.

FYI, the part number for the PSU divider is C0F3T (the second character is a zero, not an O as indicated above).

Hoping one of you see this. How did any of you solve the P4 missing on the conversion kit. I’m sure I should see it but I just don’t. 

i bought the kit and like the initial poster didn’t see it. Thanks!!

Hi. I hope you see this. I was curious how did you solve the Power 4 not there issue? I got a kit but I cannot figure out how to power the old p4 to the drives. 

thanks!!