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Scored a beat up Quadra 950

joshc

Well-known member
More progress, everything is hooked up (ignore how messy it looks), including a soft power circuit, and the power supply works !

I was a bit stumped for a while because the power supply would switch itself off after a second or so, I assumed I did something wrong or that the soft power circuit was wrong, but no... this power supply won't power on without the fan plugged in. As soon as I put the fan back in, it powered up and stayed on...

Still got to figure out a good way of putting some load on the 12V rail so that it can start without a hard drive attached but otherwise this is basically ready to go once I've done some cable tidying.

543E3312-38CA-4610-94D7-343251B4CE61_1_105_c.jpeg
 

joshc

Well-known member
Tidied it up, almost there now. I am waiting on some sticky foam tape to secure the Seasonic PSU inside the Quadra PSU enclosure and to insulate the back of the soft power board with.

Haven't figured out the 12V load issue so keeping it as is for now.

99A9E5AF-90A4-4106-8C58-E055710B8966_1_105_c.jpeg
 

joshc

Well-known member
Finally had some success with this.

Since the last time, I got the PSU all done and back together, but once it was back in the machine, it started playing up again and would power itself off. I couldn't find anything wrong with my wiring, so I put it down to the Seasonic 250 unit just being a dud.

I bought a Seasonic 350 PSU to give it another go. Annoying as I had to undo work and it's not ended up as tidy as it was the first time round, but...

Thanks to a 'new' logicboard from @slomacuser and previous troubleshooting help from @Bolle and @cheesestraws, this thing now chimes and boots, and most importantly, it stays on and nothing exploded!

Stuff remaining to do:
- Reassemble PSU and tidy it up as much as possible
- Wire the fan a different way, it doesn't run from cold because of the PSU's temperature monitor and really I'd like it to run all the time.
- Finish cleaning up the rusty drive carriers
- Fit a SCSI2SD and CD drive
- Refurb the floppy drive
- 3D print a CD drive bezel

A284F6C6-CC72-4E1B-A990-CC30E4FAE86E_1_105_c.jpeg

F31A6E4C-E1FC-4097-9F3D-56A7DA061EED_1_105_c.jpeg

4D53437F-DCDC-45F9-8C92-F387A4627D51_1_105_c.jpeg
 

mg.man

Well-known member
Stuff remaining to do...
- turn on 32bit addressing... :ROFLMAO:

Well done! ...nice when a plan comes good!! BTW, on the advice from @LaPorta, I picked up a 5L of that Evaporust stuff... not given it a spin yet, but can decant a bit and bring the next time we meet to swap bits... :)
 

joshc

Well-known member
I picked up a 5L of that Evaporust stuff... not given it a spin yet, but can decant a bit and bring the next time we meet to swap bits... :)
Ohh yes please!

turn on 32bit addressing...
Ha, well this was just a quick test from my external SCSI2SD with no PRAM battery installed. Once I've got a permanent storage solution going I'll stick Force32 on there. :)
 

Byrd

Well-known member
Nice work, shame about the first Seasonic PSU - they always seem like quality pieces of kit. I'm also assuming your Quadra 950 doesn't sound like a jet when running at full tilt It was definitely a workstation, not a home machine.
 

keehn

Member
@joshc nice work! I have a Workgroup Server 95 (a Quadra 950 but different name) that I'm restoring also. Do you mind sharing your ATX -> 950 pinout here? I got a EVGA 500watt ATX PSU that I have freed the pins on and will use as the donor PS.

I looked over the site https://www.geekdot.com/fix-quadra-power-supply/ but it appears that his plug is two pins shorter than mine (1-11 and 12-22, versus 1-12, 13-24 for mine). Thusly, I cannot rely on his schematic unless I want to play with fire (metaphorically and, quite possibly, literally). And seeing as how our 950 logic boards are near-unobtainiums, I'd sooner shadowbox the board than subject it to voltage spitballing.
 

valejacobo

Active member
Great find, big oof at that PSU and the battery. Seems like a fighter to work after all that trouble. I've remade the floppy cable for my 900, and it's a easy upgrade from the janky original ones.
Let me know if you ever plan to sell a drive caddy, since I'm looking for one to add a second unit in mine.
 

joshc

Well-known member
Do you mind sharing your ATX -> 950 pinout here?
I used the geekdot page as a guide. Yours should be the same, as I believe the WGS95 uses the same Q950 logicboard. I wasn't aware there is a different pinout, perhaps worth posting photos of yours here and somebody might be able to advise the correct pinout for you board?

Let me know if you ever plan to sell a drive caddy, since I'm looking for one to add a second unit in mine.
I only have one drive caddy so I'll be keeping that. There are probably other ways of mounting further drives (maybe with a 3d printed bracket?)
 

keehn

Member
I used the geekdot page as a guide. Yours should be the same, as I believe the WGS95 uses the same Q950 logicboard. I wasn't aware there is a different pinout, perhaps worth posting photos of yours here and somebody might be able to advise the correct pinout for you board?


I only have one drive caddy so I'll be keeping that. There are probably other ways of mounting further drives (maybe with a 3d printed bracket?)

This is what I'm talking about:
Screen Shot 2021-12-14 at 13.54.41 .png
The photo on geekdot only shows 11 pins per side of the connector. Mine OTOH, has 12 as shown below:

IMG_0650.jpg

The logic board SAYS Quadra 950:

IMG_0569.jpg

So I'm scratching my head here trying to figure out why geekdot's power connector is only 22 pins, but mine is 24 pins.

Any words of advice or encouragement?
 

Johnnya101

Well-known member
This is what I'm talking about:
View attachment 36929
The photo on geekdot only shows 11 pins per side of the connector. Mine OTOH, has 12 as shown below:

View attachment 36928

The logic board SAYS Quadra 950:

View attachment 36930

So I'm scratching my head here trying to figure out why geekdot's power connector is only 22 pins, but mine is 24 pins.

Any words of advice or encouragement?
Am I misreading it, or are there twelve labels, but only eleven pins in the drawing?
 

joshc

Well-known member
Yep, it’s a 24 pin connector, the diagram is just missing two pins but the labels are right.
 

keehn

Member
Yep, it’s a 24 pin connector, the diagram is just missing two pins but the labels are right.
*Facepalm*. I was so focused on the drawing that I didn't bother counting the actual colors listed far left and right of the diagram.
 
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