Fuel ATX PSU Conversion


irix detailer
Feb 8, 2019
This documents my recent Fuel ATX power supply conversion. I had a chance to get a Fuel with a bad PSU, and so I needed to power up my new Fuel! These are the things I researched, parts that I got, and the procedure I took for a successful installation of a new ATX PSU for my Fuel. The swapping of the wires in the 24pin harness was the most difficult part, but over all it's much easier than having to try and fix one of the older and completely custom SGI power supplies.


ATX Fuel Manual:

ATX Pinout Image:

Purchased Equipment:

StarTech.com EPS 8 Pin Power Extension Cable

StarTech.com 8in 24 Pin ATX 2.01 Power Extension Cable

Rosewill Quark Series 1200 Watt


- remove bad PSU, set aside
- take 24 Pin ATX 2.01 Power Extension Cable and re-pin according to Wiki Page on PreterHuman (see images below on re-pinning)
- take 8 Pin Power Extension Cable and re-pin according to Wiki Page on PreterHuman
- read the wonderful Manual from Kuba Tyszko to get a feel of how you will test in stages
- connect a 9pin serial to L1 port on MB and attach to terminal
- connect 24 pin and new PSU, enable power and check L1
- connect 8 pin and enable power and check L1 voltages
- disable env monitoring
-- env off
- power on fuel
-- pwr u
- check L1 terminal for proper voltages and thermals
- power down system if there are issues
-- pwr d
-- If things are good, attach drives and power cables for drives and power up fuel.
- Having a terminal on Serial 01 port also helps to see long power-up sequence (flashing white light)
- When light goes solid Fuel should be booting
- Mount new PSU in Fuel with screws and do wire routing
- Close up case and enjoy your fuel
- Continue to monitor the thermals via L1 cable (recal env monitors are OFF)
-- System could overheat and not automatically shutdown



Equipment from Amazon


Take 2 staples, straighten out. Insert on each side of the male pin. push down snuggly, pin should pull out easily.
If it does not pull out the staples are not aligned, pull them out and re-insert.
Trust me, you will do this so many times you become an expert at feeling when it's correct and they come out faster.
At first it's difficult to get it right. Keep trying.


Examine Voltages via L1 termainl using env command. Verify all 3/5/12 look good


Testing new PSU, these are the power extenders which are re-wired. The rest of the PSU is not changed.


Success! Fuel posted and went into Console so I could get a HINV.


New PSU mounted and screwd in


Cables guided in and ducting put back


Full boot into IRIX w/ new PSU


Always watch envs and monitor therms.

You can see there FAN 5 - the PSU fan - the Fuel knows nothing about this now and this is why we must disable env monitoring.
Last edited:
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Feb 4, 2019
The staple pin pusher is a great trick! I haven't verified that these are absolutely the correct ones because I don't have them, but there are also the tools in case one wants to speed up the process:
If that sounds expensive then the staple is probably the best option! Because one could always buy the TE 318831-1 for $248.88 on DigiKey ;)

Knowing China of course, there are probably aftermarket options at 1/10th the price of the first two on AliExpress.


New member
Jan 29, 2020
Oh nice. I see that on the first VT screenshot you caught it before the L1 got to shut the Fuel down due to monitoring enabled ;).
I like how your VT510 shows the text. My WYSE-160 really doesn't like L1 output and shows is very garbled.

That reminds me, my manual needs some updates, I'm going to show current generation of the adapter (red board) and probably remove those defunct nekochan links :(

Enjoy your Fuel and thanks for the acknowledgements.
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