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Scored a beat up Quadra 950
Posted by: joshc on 2021-10-11 01:49:07
Finally bought a Quadra 950. It's beat up, the Maxell battery did some damage to the RAM/RAM slots, and its very dirty. Oh, and it has a 601 card.

It arrives later in the week. Fingers crossed I can get it going again.

Some photos from the eBay listing...

1633941971634.png



1633941993822.png

1633942066226.png
Posted by: ArmorAlley on 2021-10-11 03:58:17
Congratulations. I do hope that the damage from the PRAM battery can be repaired.
Be warned, however, about the power supply. These things are on their last legs. They are loud too.
@BadGoldEagle has a great thread on rebuilding the PSU from the Q950.
Posted by: joshc on 2021-10-11 04:00:24
Thanks. Yep, I'll be using it with a switched power strip. I am not going to attempt powering it on until I have inspected everything and repaired any damage from the battery.
Posted by: slomacuser on 2021-10-11 04:24:37
I have extra 950 board, so If you need it let me know 🙂
Posted by: joshc on 2021-10-11 05:59:28
I have extra 950 board, so If you need it let me know 🙂

Thanks. Hopefully I can fix this one, but if I get stuck I will be in touch!
Posted by: Unknown_K on 2021-10-11 13:39:59
I think you are lucky that the battery exploded in a board that is vertical so the acid just slides down and doesn't pool. RAM sockets and RAM are easier to replace then finding broken traces in a multi layer board.
Posted by: mints on 2021-10-11 14:20:57
A fellow recent acquirer of a 950! I hope that your road to getting it up and running is painless.
Posted by: joshc on 2021-10-12 11:51:09
It arrived today. This thing is an absolute unit... It's huuuuuge!

As expected, battery damage to the RAM slots and some of the RAM.

The battery and battery holder came off the board together but underneath it doesn't look too badly damaged.

The case has some battle scars. And some of the clips on the side door snapped off, but I have the plastic bits to glue back on.
Posted by: mints on 2021-10-12 18:37:39
Is that the WGS PDS Card? It doesn't look like the PPC Card and I don't think they made many other cards for the Quadra PDS slot.
Posted by: Byrd on 2021-10-12 19:09:38
@mints No the WGS card is a huge beast - takes up almost the entire length of the top (PDS) slot.

Looks good, and serviceable - I'm sure you'll be the man who can revive it joshc! 🙂
Posted by: mints on 2021-10-13 12:29:24
@mints No the WGS card is a huge beast - takes up almost the entire length of the top (PDS) slot.

Looks good, and serviceable - I'm sure you'll be the man who can revive it joshc! 🙂
Ah ok, I started to get excited that maybe his pick up was even better than he thought initially.
Posted by: joshc on 2021-10-13 23:46:04
Nope, just the 601 card which I've cleaned/redone the thermal paste and it's working in my Q700.
Posted by: lobust on 2021-10-15 11:08:24
Nope, just the 601 card which I've cleaned/redone the thermal paste and it's working in my Q700.

I was watching it on ebay too, and had the exact same intention of using the 601 card in my 700 if the 950 was truly a gonner - decided I didn't need any more projects in the end!

Good to see it's in capable hands!
Posted by: joshc on 2021-10-18 16:01:29
Damage report. Tried to power the Q950 on. Fizzing from the PSU and then once I pressed the power key it did start up, no chime but it was running. And then 30 seconds later there was a pop from the PSU and it died.

Started to investigate, pulled the PSU apart and, well, it looks like the Titanic in there...

E40A2082-4DAB-442A-9740-FE5BC81B82AF_1_105_c.jpeg

Fully opened up, it doesn't look quite as bad but I cannot see anyhing obviously exploded here...

Fuse *looks* ok but I haven't tested it yet.

2644FE00-D84E-4DEF-85A9-328CE1639FFB_1_105_c.jpeg

So I guess I'm at crossroads here. Attempt to fix the original unit, or replace with a modern ATX PSU and do a conversion?
Posted by: cheesestraws on 2021-10-18 16:53:38
You could try to fix it, then when it inevitably fails you can replace the innards without feeling guilty about it? 🙃
Posted by: Byrd on 2021-10-18 17:12:48
So I guess I'm at crossroads here. Attempt to fix the original unit, or replace with a modern ATX PSU and do a conversion?

I'd be included to say try, but looking at what appears to be moisture damage (from the dust clumping on the components and rust), I don't think you'll get far. Maybe a deep clean of the crud and it'll come up looking OK, but still not trustworthy.
Posted by: Unknown_K on 2021-10-18 19:11:41
You could be lucky and it is just a fuse blowing. I assume that the unit was sitting long enough to dry out before you turned it on. Could be a short on the board causing the problem.

Blown voltage regulators tend to toss plastic bits around and have burn marks they are are easy to spot (once you get that dirt off them).
Posted by: mg.man on 2021-10-19 02:38:22
NO experience with these... but a quick glance spotted a few things...

JC Q900 PSU.jpg

1) orange rings -- seem to be missing components? maybe they were never there?
2) yellow rings -- can't make out what those are / are supposed to be?
3) red ring -- can't make out that that is sticking up?

Also... the 'mains (brown / black) connector at the bottom right is unplugged - but assume that's your doing?

Good luck!!
Posted by: joshc on 2021-10-19 02:55:05
Thanks all.

I've bought a cheap, but what appears to be adequate, Seasonic modular server 400W ATX PSU to use as a way to test the logic board. It may even be good enough for a permanent solution as it has a fairly strong 5V rail and two strong 12V rails. I could hook up a DC to DC converter to create an even stronger 5V rail from one of the 12V rails.

1634637081522.png

The rough plan is: remove the 40mm fans from this server PSU, use the original Q950 PSU fan instead, hook up a little circuit for soft power, rewire the ATX connector, and re-use the Q950 secondary PSU PCB with the 5V sockets on it to keep it looking stock from the outside of the PSU.

The original PSU is completely unknown to me, I don't think schematics are available, and I don't want to waste time/effort on it.
Posted by: Renegade on 2021-10-19 06:05:12
I've bought a cheap, but what appears to be adequate, Seasonic modular server 400W ATX PSU to use as a way to test the logic board. It may even be good enough for a permanent solution as it has a fairly strong 5V rail and two strong 12V rails. I could hook up a DC to DC converter to create an even stronger 5V rail from one of the 12V rails.

The rough plan is: remove the 40mm fans from this server PSU, use the original Q950 PSU fan instead, hook up a little circuit for soft power, rewire the ATX connector, and re-use the Q950 secondary PSU PCB with the 5V sockets on it to keep it looking stock from the outside of the PSU.

The original PSU is completely unknown to me, I don't think schematics are available, and I don't want to waste time/effort on it.

@joshc , have you checked @BadGoldEagle 's current project? It's very similar to what you intend to do and could save you some time.
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