I'm sure that there is a good explanation for this, but it eludes me.
My Quadra will turn on from the key switch and from the keyboard (both normally), but I get no boot chime. I also get no video picture on the monitor. The configuration was as follows:
[slot A$]Pro Audi Spectrum 16 Sound card
[slot B$]Video Vision Studio card
[slot C$]FWB SCSI JackHammer card
[slot D$]FWB SCSI JackHammer card
Drives (bus1)
[*]SCSI RW CD
[*]SCSI CD (caddy)
[*]SCSI 5 CD changer
[*]floppy
Boot disk was a Mac OS 8.1 CD. all device IDs were valid and unique. no other drives were installed. Th machine would not respond, so I stripped it of everything but a standard tray loading SCSI CD (with the 8.1 disk - something I have been able to boot off of before). The machine behaves the same. I have removed all power (even the battery) and let it sit. The machine was sitting for a few weeks un used (off) prior to all of this. It is plugged through AC protection circuits.
I cannot find what caused the machine to turn on me. any ideas?
--DDTM
Hey,
Try a fresh or known good pram battery.
william
Try swapping the memory?
I will check the voltage on the battery later today.
--ddtm
I have nothing to swap it out with. The memory in there is what was in when it was working.
--ddtm
Oh, okay. Memory normally is either good or bad; rarely changes. Try re-seating all the cards and stuff in general, then.
Well, the voltage on the 3.6V battery is bouncing between 2.5 and 3V. As soon as a store is open, I will replace the battery and see where I am at.
Thanks!
--DDTM
Is it booting yet?
...but I do have the battery in my pocket right now and will be stopping by the store on the way home from work. I am off tomorrow and plan to work on it right after I finish the one eMate I have left in my to-do pile (at which point the bench will belong to the Quadra). I really hope that this is all that the problem is.
--DDTM
I got a new battery and put it in. The behavior is unchanged. The speaker still spits out static and is apparently nothing more than a paper weight with a green light.
I had removed the mother board prior to the new battery in order to inspect it for a failed component. Their is nothing readily discernable about the board that would indicate a failed capacitor or resistor or anything else like that.
Any other ideas?
--DDTM
Have you tried booting it without any drives attached and all nubus stuff removed?
Do you think the Power Supply could be hosed? If you can power it from another mac's PSU, then do it. I know there are people out ther who use PSU's from other mac series, and they work. ( I think I used a 7200 PSU in an 8100 before, I can't remember) I myself am using an off-the-shelf PS to replace a PowerComputing PS that was sending 120v through the case. (I guess it was grounding the positive to the case. Boy did I get a electrical Buzz off of that. Anyone else had prob. with the PCC PC's)
EDIT: I am so surprised that no actually asked this question!!
...the current config is no cards, the RAM (can't remember how much it is), and only a CD ROM wih a 8.1 CD (floppy drive removed also).
--DDTM
The only other PSU I have is an extra (dead iMac) and I do not see that working here. The PSU seems okay, fan runs, no noises, no smells. Being that I am finishing up the emates, the workbench will bee free in the next week or so. I have better equipment there (as opposed to the back office). I will search for he output specs and compare the voltages on it to see if it is okay. Right now i do not think the PSU is the problem as I have no real proof that there is an issue there.
--DDTM
I pulled the PSU off (again) to see what the problem was and reinspect the board and such and found this...
http://www.applefritter.com/node/view/5810
...and this after my insisting that I had inspected it good (next time i will use a flashlight when I check as room lighting was obviously inadaquete).
Now the question is why did this happen?
Thanks for all the ideas folks, it helped.
--DDTM
If you had it on the circuit (i think you said it was on a protection circuit) it might have had a surge. Check on the circuit and see if it has a light that when on. It's not a garuntee that it won't surge, just a warranty. You probably could solder a wire from the PSU Cord to the beginning of the trace route on the board using a wire wrap (you would have to find wire wrap that could carry the current and Voltage.) I hope you can resolve this, as I would hate to see a quadra board go into the trash-heap that is perfectly normal excpect the fact that it could be modified slightly to work.
So go get that Soldering Iron out and get going!!!!
yeah, I am going to follow the path and see what other things are along the path and if they may have been affected to. Something took too much power for sure, if it was just a trace, then I need to find and eliminate the source of the spike. As i had everything hooked through surge protectors, I am wondering if it was something on the hardware side as I have several cards and drives I am trying to work into the same box.
--DDTM
... a burned out trace like that is usually an indication of something downstream that caused an over-current condition, and the trace acted like a fuse. If you can find and replace the culprit, you might be able to salvage it.
Otherwise, think "case mod" dude!
Bummer. You have my sincerest condolences.
That was most likely not caused by a surge... As the last person said, most likely a short circuit / over current.
Check transistors, caps etc.
Hi,
I had the same problems with my Quadra 950.
I have almost the same configuration as you do.
I had a FWB JackHammer, a VideoVision Studio pro,
a Digidesign Audiomedia Card II and a Radius Precision Color Pro 24 X.
The machine suddenly produced the same problems as your machine.
I have identified the problem in the FWB Jack Hammer card.
I have 2 of them as you do, but only one is working in my Quadra!
Therefore I decided to get an Atto Silicon Express IV. This card really rocks- no problems at all and much faster!
But first: disconnect all NuBus cards, all SCSI peripherals. Then swicth on the Mac- the Mac should show the question mark afterthe screen test- and replace the Pram battery first- unplug all power cables and let the Mac sit for a few hours... at least 30-45 minutes. Then start the Mac without the battery first- you can install it afterwards.
Then systematically insert one NuBus card after the other.
The JackHammer card seems to be very slot sensitive.
And: flash your JackHammer card!
Tell me how you succeed...
Helmut
when I posted the bad boy comments. (he is using my computer and causing havock.) (he even sent a nasty letter to tom owad. using my email address. (i am truly sorry!! Tom) I will be monitoring him closer. If he does something like this again, he will never use my computers again. (or I will create a special account with lockdown privialeges. In fact i will do that after I get down writing this!!!) maybe we need to ban his account?
Well, I fixed the trace by soldering a piece of wire to bridge the gap. (I will post pics later.) The idea of putting a fuse in-line was okay, but I had trouble locating what I needed at any local retail stores. I could have ordered a part from a catalog or online, but I could not satisfy minimum purchase requirements to make such a thing feasible. Besides, I realized that it would work better if I put a fuse on the line between the PSU and the mobo connector vice on the mobo directly as previously imagined.
The machine boots up to the ROM, it will most likely continue to a full boot once I reinstall the drives.
--DDTM
well, I had added some cards and a drive or two. I had a floppy, two SCSI drives on the mobo bus, two FWB Jackhammers, a PAS 16 card and a VVS card. The trace blew again. This time I know it happened when I put the VVS in. I think the card is bad. I repaired the trace (again), but it is still dead. I will re-inspect the board and see if there is anothe failure. When it goes back together, the VVS will be left out and quarantined to a different machine. The trace in question is supposed to handle 5Amps, but I question that after this. This can have some design considerations for my ECC. I will definetly consider a direct power feed to the card from the PSU because it is clear that I will have some power draw problems with just a few NuBus cards (of course I suspect the VVS card is bad - it was known to work well for the previous owner, whom I have no reason to doubt).
--DDTM
The repair I made is good, but there are some traces on the back of the board which have gotten hot and caused their green coating to flake off. The affecteed trace feeds some NuBus pins. I cannot locate a break in any traces just yet, but did note that the circuit path is somehow shorting out to ground...
I can already see that I may have to remove the connector for the PSU and re-do my work on that trace. While it works, it is too ugly for my taste.
--DDTM
After destroying the PSU connector and snapping three of the pins in its removal while trying to repair a phantom burned trace, I have discovered that my coninutity tester may be lying to me. Some circuits I know to be good are readin on the meter as shorting out, indicating that there may not be a short on the mobo after all. And there was not a short/burned trace under the connector as strongly suspected and indicated by the continuity tester.
I will repair the thrice-damaged trace and attempt to 'repair' the mangled connector.
We will see where it goes from there.
Well, I got a new machine from Xanthus (over in the barracks). So I will canabalize what I can from my original Q950.
I am convinced that the problem was caused by the VVS card. This is sad 'cuz I had plans for that.