Q950 restoration project

[CompuNurd]

I'm frustrated to say the least.

Why? Let's start from the beginning. I finally got a case for my various 950 parts that have been sitting for a while unused. I put them all together, and I get a chime, then an immediate death tone. It did this from the start. I removed some cards to connect a cable, then when I turned it on again... POP! I blew something on a card. As to how I did it, I don't know.

Here's the card. The blown part is near the screwdriver tip. That small card came off of the top two cards.



Remember, I have no idea what anything on the board is. I have never touched one of these things before. It will not display anything, and I don't think it did before I blew the card either. I have no idea what to do next. There is no sound coming from the speaker now, just a pop when you turn it on.

 

[techknight]

Ouch. Something didnt get plugged in correctly, or 1-tooth-off. They usually dont blow for no reason. 

That looks like it was part of the video capture subsystem which is probably screwed now. So i would leave it all out, and just put a known good graphics video card in it and give it another shot. 

If that doesnt work, then theres a good likelyhood the nubus controller or one of the buffer transceiver ICs on the databus is dead. Lets hope not, because it looks like that logic board uses all custom ICs for these jobs unlike the older stuff. 

 

[CompuNurd]

I don't have anything other than what you see in the photos. I tried plugging it into a monitor from the d19 plug on the back of the motherboard, and nothing happens.

 

[techknight]

then there is a good likelyhood the motherboard is toast now. 

But, to be sure you can try measuring the voltages coming in from the power supply and make sure your not missing one. 

 

[CompuNurd]

I'll do that a bit later. It's put away right now. Does the Q950 have on board graphics, or could it have been part of the card I just blew?

 

[MinerAl]

I'm pretty sure it has onboard video.

 

[Unknown_K]

You need to know what you are plugging cables into before you do it.

The RAM banks are spread between top and bottom (not in a row). So 2 RAM SIMMs top and 2 on the bottom or you get memory errors and sad mac.

 

[CelGen]

It ain't easy to incorrectly plug the PSU's power cable in unless you are a gorilla, so the possibility that you were pushing volts into somewhere it shouldn't be and blowing up IC's and components is unlikely. Also the 950 has onboard video so you can pull all your cards out and you'll still have an onboard source. In fact, with all NuBus and PDS cards removed and just one bank filled with ram you should get a chime.

While the machine no longer chiming isn't a good start it could of been something as easy as a tantalum capacitor shorted out and yes, I have seen them short out between immediate recent power cycles with absolutely no warning (and this could of been what blew on the NuVista because I can't see ANY damage to that board).  I'd recommend trying to run the machine completely stripped to the basics (no hard dirve or floppy drives attached either) and see what happens. Also pull the machine apart if you prefer and see if you've accidentially left a screw somewhere that rolled under the logic board because yeah, that will kill it.

Also, don't dump the cards just yet. Avid boards are rather nice if you're into old fashioned capture rigs, especially if they have the compression board. If you do plan to dump them regardless, talk to me because I'm setup to better verify if indeed the boards are dead or not (plus I have spare cables and the likes). Heck, if you want to send the whole logic board I can test to see if it is still working as I got all the tools needed to better analyze if things like the clock and the Bus controllers are still doing anything.

 

[Elfen]

Maybe I should send you my LC475 board, CelGlen - It bongs and then nothing! I so want that LC up and running! LOL...

But seriously, like CelGlen stated, test the Q950 buck naked - no drives, no cards, nothing but RAM. See if it bongs and gives video. 

I have that exact same card (probably came from the Q950), and that daughter board is a video compressor, as the car can run without it but without compression. It also came with a separate NuBus card for sound (6 channels) but they look like they need a recapping. And maybe I should take my Q950 out of storage and test it. I'm still worried about the case as it is cracked through in many places as it was dropped out of a 4 story window long ago. You need software for these card, which I do not have; but since they add function to the Q950, you can run the Q950 without them.

I hope you can get it fixed, even with help.

 

[Schmoburger]

Maybe I should send you my LC475 board, CelGlen - It bongs and then nothing! I so want that LC up and running! LOL...

But seriously, like CelGlen stated, test the Q950 buck naked - no drives, no cards, nothing but RAM. See if it bongs and gives video. 

I have that exact same card (probably came from the Q950), and that daughter board is a video compressor, as the car can run without it but without compression. It also came with a separate NuBus card for sound (6 channels) but they look like they need a recapping. And maybe I should take my Q950 out of storage and test it. I'm still worried about the case as it is cracked through in many places as it was dropped out of a 4 story window long ago. You need software for these card, which I do not have; but since they add function to the Q950, you can run the Q950 without them.

I hope you can get it fixed, even with help.

I had a 475 that did the same thing Elfen, and it turned out to be bad pin rot from leaking caps on a fairly significant chip (can't remember which one but suffice to say it was stuffed. At that particular time I had no real interest in the 475 and had one that worked fine so I beleive I just threw the board away. unfortunately, that one that worked was the same one that I posted in the battery explosion thread some time ago now which had a cataclysmic explosion under the lid during a period of storage, which would have made that junked board seem a breeze to repair in hindsight...

 

[CompuNurd]

The NuVista was smoking after the pop. I removed what appeared to be a charred component which is what the screwdriver is pointing at. When I get it out again I will try the suggestions some of you have given.

 

[Elfen]

Pull out the PSU and inspect the Q950 board. Make sure there are no burnt traces on the board.

It has onboard Video to connect to a monitor. The Nuvista card was for video processing. Many Q950s ended up in media creation houses but it will run without it. Thing is you need the software and drivers for it. They are great for a lot of things as is, but games, it might be too fast for some games.

The logic board slides out like in the IIcx/ci and LCs - with the front of the machine to you, pull the board towards you and then pull up from the front end. Put it bak together the same way.

I hate Death Chimes. Take all the RAM out of the Q950 and test them on an LC/LCII. If the RAM works, then its the video RAM SIMMs, test that next with the LC/CLCII. I think there is RAM on the board to test it without SIMMs, if not I'm confusing it with the VRAM that is built-in there, just put in 4 SIMMs into "Bank A" to test it (2 on side and 2 on the other). Both RAM and VRAM can give Death Chimes so you have to test what you got. It should be 80ns or faster RAM. I have a video card that gives death chime to any machine I put in it and I have yet to figure out where the problem is.

 

[Pandamac]

I'll do that a bit later. It's put away right now. Does the Q950 have on board graphics, or could it have been part of the card I just blew?

The Quadra 950's had basic graphics on board but most people found them inadequate. I have several Nu Bus graphics card. One drives a big 20" Apple monitor at millions of colours.

I'm trying to think of the brands without going upstairs and looking but by majority they were very long card and most had ram slots to increase the graphic capability.

My favourite is a crd by radius