Indigo² ATX PSU Conversion

For discussion of triage and repairs to SGIs as well as general hardware questions
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Indigo² ATX PSU Conversion

Post by GRudolf94 » Mon Jul 02, 2018 3:21 am

:Indigo2: Hello again, everyone. I've revised part of my stuff and the one of the ugliest Indigo² to survive is sort of alive again.
Will still not complete the selftest, I suspect it is missing one or two voltage rails I haven't figured out the pinout for just yet. It does successfully complain about missing RAM on the serial console, or a bad RTC/datapath test fail if I pull the NVRAM (that is, if failing can be considered a success). Well, any result is better than no result.

As soon as the thing is done, I'll release an adapter, or at least the documentation to make your own. Also important, :Indigo2_IMP: IMPACT people will want their MARDIGRAS cards to work, so I'll have to figure out something that will supply the over-30A current on a 3.3V rail using a regular ATX PSU, and find out the type of connector and cable used for the IMPACT rail (it's made by AMP, but I couldn't find a series). Running a base XZ system already is pretty demanding for new ATX units, so I'll probably end up making a full docset with recommendations and perhaps a list of suitable models. Note from the cable clutter hehind the HDD cage that a modular unit would've been the ideal

Please excuse the beaten-up case, no front door, mismatching skins, and no drive sleds, this was a junkyard rescue by a good friend that gave it to me.

I'll let the pics speak for themselves for now

The overall innards:

Close-up of how the PSU sits directly above the wires, invading the motherboard's space a bit. It is sitting atop the gutted shell of an OEM ZyTec PSU:

Fugly AC cable routing:

It does close and power on!
Last edited by GRudolf94 on Mon Jul 02, 2018 12:02 pm, edited 1 time in total.
:Indigo2: R10k@195MHz/64MB RAM/XZ/ATX PSU conversion in the works/acting up
:Indy: R4600@133MHz/128MB RAM/XL-24/Gruesomely plasti-welded together
:Octane: R10k@225MHz/1536MB RAM/SSI

SGI Ultra64...erm, Nintendo64 console :D

and lotsa non-SGI stuff

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Re: Indigo² ATX PSU Conversion

Post by Trippynet » Mon Jul 02, 2018 7:23 am

Nice work!
:Indigo2_IMP: R10000 195MHz, 384MB RAM, SolidIMPACT, 36GB 15k & 300GB 10k drives, new/quiet fans, IRIX 6.5.22
:Fuelb: R14000 600MHz, 4GB RAM, V10 Graphics, 72GB 15k & 300GB 10k drives, new/quiet fans, IRIX 6.5.30
:O2: in storage...

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Re: Indigo² ATX PSU Conversion

Post by gijoe77 » Tue Jul 10, 2018 10:20 am

This is fantastic! Very awesome

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