PowerMac G4 QS boot issue

amedias

macrumors regular
Original poster
Feb 9, 2008
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Devon, UK
Wondering if anyone can offer any insights here...

I have a G4 Quicksilver 800MHz that has developed a boot issue.

Symptoms:

> Will power on and into OF fine
> Will power on with no drives attached to flashing folder
> Will power on with drive attached, finds the drive, get an apple logo for beginning to boot OSX and then immediately panics with a black box overlay and powers itself off

Things I have done:

> Removed all additional drives and PCI cards - no change
> Replaced PRAM battery (and also test with it removed) - no change
> Removed AGP card and tested with known good PCI video card from my G3 - no change
> Removed all ram and tested each stick individually in each slot - no change
> Tested with known good ram from another machine, (2 sticks) tried in each slot one by one in turn - no change
> Tested with known good HDD from another machine on both IDE channels (optical and HDD) - no change
> Tested with PCI IDE controller from the G3 to rule out the onboard IDE - no change
> Tested with known good IDE cables from another machine - no change
> Removed and re-seated processor daughter card and re-applied thermal paste - no change

> Removed on-board modem module - Eureka! it booted into OSX and was stable for ~4 hours before I shut it down deliberately, BUT then I attempted to power it back one and back to same issue, so appears to have been a random fluke boot :-(

Any suggestions?

I'm starting to suspect either bad CPU or bad logic board, but don't really want to splash out on replacements for either (which more likely?) if there are other things worth trying first.
 

Raging Dufus

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I don't think it's your CPU or logic board; your machine is passing P.O.S.T. so they're probably fine. If I understand you correctly, it's only when you try to boot into an installed OS that you have an issue. I can't account for the difference from removing the modem.

Tested with known good HDD from another machine on both IDE channels (optical and HDD) - no change
What's on these HDD's? Are they clones of each other, or does each have a different OS...or at least, a different installation of the same OS? What is the OS that you're trying to boot into? It seems to me that your problem lies there, with a corrupted install or perhaps some issues with extensions - depends on which OS we're talking about. A fresh install might solve your problem.

Since you have another Mac, have you tried booting from both HDD's in that one? Do they both work in that one?

Have you tried to boot your Quicksilver from either of the HDD's, while they're in your other Mac, by using Target Disk Mode?

Lastly, have you tried booting your Quicksilver from its own optical drive, using a Mac OS installation CD/DVD?

You've been pretty thorough in troubleshooting, but these extra steps may help isolate the problem.
 
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amedias

macrumors regular
Original poster
Feb 9, 2008
186
158
Devon, UK
I don't think it's your CPU or logic board; your machine is passing P.O.S.T. so they're probably fine. If I understand you correctly, it's only when you try to boot into an installed OS that you have an issue. I can't account for the difference from removing the modem.
I am pretty sure the successful boot after removing the modem is nothing but random fluke, but it seemed worth including for info as it is a bit peculiar!

What's on these HDD's? Are they clones of each other, or does each have a different OS...or at least, a different installation of the same OS? What is the OS that you're trying to boot into? It seems to me that your problem lies there, with a corrupted install or perhaps some issues with extensions - depends on which OS we're talking about. A fresh install might solve your problem.
The original HDD I tested with has a 10.3 and a 10.4 install on it, neither would boot, but both WILL boot in my G3 and in my gigabit ethernet DPG4 (when it has a working PSU, which it doesn't right now!). I also tried the converse of using the known working disks/installs from the G3 and DPG4 and I get the same behaviour. Basically the constant is that nothing will boot in the QS G4, (except that one time it worked after removing the modem!).

Admittedly none of them are 'fresh' installs but they are known working installs with no unusual modifications or hacks involved.

Since you have another Mac, have you tried booting from both HDD's in that one? Do they both work in that one?
As above, yes I have tried that.

Have you tried to boot your Quicksilver from either of the HDD's, while they're in your other Mac, by using Target Disk Mode?
I have not tried that, good shout, worth a try...

Lastly, have you tried booting your Quicksilver from its own optical drive, using a Mac OS installation CD/DVD?
I have not as the currently fitted optical drive is dead as a dodo. I'll see if I can scavenge one out of one of the other machines and locate an install disk.
 
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Raging Dufus

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Since your other Mac is a Digital Audio, there's a quick and easy way of determining whether the problem is your Quicksilver's CPU. Just swap out the CPU modules. Your DA's CPU will slot right in to your QS's logic board, the heatsink should fit, and since both machines have a 133 MHz system bus it should even operate at the same speed in the QS.

Assuming you're confident that the DA's CPU is good, of course.
 

amedias

macrumors regular
Original poster
Feb 9, 2008
186
158
Devon, UK
Since your other Mac is a Digital Audio, there's a quick and easy way of determining whether the problem is your Quicksilver's CPU. Just swap out the CPU modules. Your DA's CPU will slot right in to your QS's logic board, the heatsink should fit, and since both machines have a 133 MHz system bus it should even operate at the same speed in the QS.

Assuming you're confident that the DA's CPU is good, of course.
It's not it's a Gigabit Ethernet with dual 450s, my post was me typing mistyping 'DP' as 'DA' and then not deleting when I corrected it, sorry for the confusion, I have now corrected my post.

I did have a look in my spares and all I could find was a 400Mhz G4 from a 100Mhz bus machine, otherwise I would have swapped CPU when I had the 800Mhz one out for re-seating.
 

AphoticD

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Can you boot while holding Cmd-V then take a photo of the kernel panic log? This might help to troubleshoot.

Also it might be worth trying to boot into safe mode by holding shift.
 
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Raging Dufus

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It's not it's a Gigabit Ethernet with dual 450s, my post was me typing mistyping 'DP' as 'DA' and then not deleting when I corrected it, sorry for the confusion, I have now corrected my post.

I did have a look in my spares and all I could find was a 400Mhz G4 from a 100Mhz bus machine, otherwise I would have swapped CPU when I had the 800Mhz one out for re-seating.
OK, take this advice at your own risk, but you can still swap them. I've done it before without ill effect.

It's not a perfect test obviously, because the spare G4 CPU's you have were meant for a 100 MHz bus. The dual 450's will run at ~600 MHz in the QS, and the single 400 at ~533 MHz; and they may cause a kernel panic simply because they weren't meant to run that fast. However, depending on the quality of the particular chips involved, they may just boot up and run without problems. It's hit and miss, you won't know until you try.

The only thing is, you won't be able to close up the QS because of the different heatsink configurations, you'll have to run it open. If you only do so briefly, no harm should result.

I say again, do this at your own risk! I can't guarantee no harm will result, all I can tell you is that I've done it myself, and if I were in your situation would not hesitate to do so again.
 
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amedias

macrumors regular
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Can you boot while holding Cmd-V then take a photo of the kernel panic log? This might help to troubleshoot.
I will try this, not at home with the machine right now so taking in all the advice and will try things when I'm able to mess with the machine, will report back...

Also it might be worth trying to boot into safe mode by holding shift.
I have tried that, forgot to add it to the list![/QUOTE]
[doublepost=1549555765][/doublepost]
OK, take this advice at your own risk, but you can still swap them. I've done it before without ill effect.

It's not a perfect test obviously, because the spare G4 CPU's you have were meant for a 100 MHz bus. The dual 450's will run at ~600 MHz in the QS, and the single 400 at ~533 MHz; and they may cause a kernel panic simply because they weren't meant to run that fast. However, depending on the quality of the particular chips involved, they may just boot up and run without problems. It's hit and miss, you won't know until you try.

The only thing is, you won't be able to close up the QS because of the different heatsink configurations, you'll have to run it open. If you only do so briefly, no harm should result.

I say again, do this at your own risk! I can't guarantee no harm will result, all I can tell you is that I've done it myself, and if I were in your situation would not hesitate to do so again.

I have no qualms about running the machine open for a while, I can even get decent airflow over it with external fans.

I'd not bothered sticking the spare 400 in as I assumed that the 100-133 overclock would be too great for it to handle and and if that panicked as well then I'd still not know if it was the QS CPU that was duff or not, but I guess it can't hurt to try. my G3 is a 300 OC'd to 450 and has been rocks solid stable for about 7 years so sometimes big OC's do work fine, but that was a multiplier OC rather than a big bus OC.
 
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amedias

macrumors regular
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So, updates....

- Verbose boot - no luck, it powers itself off too quick to catch
- Boot from optical - no luck, it either hangs indefinitely or panics like with HDD
- Target disk boot - pending as believe it or not I can't find a single FW cable in the house so will get one during the week.

Additional development though, I bought a Digital Audio 533Mhz off a guy this weekend for almost nothing, and it's in full working order, so might be a safer bet for CPU trials?

I think the 533 DA CPU will work just fine in the QS, but would the QS CPU work in the DA ok? I know they're the same bus and socket, and pretty much same generation as there was a 733Mhz 7450 version in both QS and DA...but there's also that extra 4pin output from the PSU in a QS and I thought I read somewhere that this was necessary and that there was a 12v feed into one of the processor card mount pins on the QS which makes me think it wouldn't work in the DA? Unless I take a 12v feed from a HDD molex...hmmmm
 
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Raging Dufus

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I think the 533 DA CPU will work just fine in the QS, but would the QS CPU work in the DA ok? I know they're the same bus and socket, and pretty much same generation as there was a 733Mhz 7450 version in both QS and DA...but there's also that extra 4pin output from the PSU in a QS and I thought I read somewhere that this was necessary and that there was a 12v feed into one of the processor card mount pins on the QS which makes me think it wouldn't work in the DA? Unless I take a 12v feed from a HDD molex...hmmmm
The DA CPU should work without modification in the QS.

The QS CPU will work in the DA, with a small electrical mod. You'll need to bring 12V power to the 4th mounting hole on the QS CPU's daughter card. You'll find a discussion of this issue here and here (the second link is thru the Wayback Machine, and discusses using a QS CPU in a Gigabit model, but the principles are the same).

Also, see below for pics of my own mod to make a 933 MHz QS CPU work in a Sawtooth (again, same principles).

IMG_20190210_151858006.jpg


IMG_20190210_152022826.jpg

The yellow wire in the above pics is standard 12V wire cut from an old PSU. I soldered a ring connector on one end and attached that to the 4th mounting hole in the CPU card with a short bolt & nut. Then I soldered a sleeved male connector to the other end, which plugs into a sleeved female connector spliced into a standard Molex plug's 12V wire.

You don't have to do something so permanent as what I've done, I only went to the trouble so it would be easier to install/uninstall the CPU: just plug/unplug the connector. Whatever method you choose, just be sure that your power connection isn't touching anything else above or below the CPU card. See the next couple of pics, I used a very short bolt and nut:

IMG_20190210_154407624.jpg

IMG_20190210_154418167.jpg
 
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amedias

macrumors regular
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Thanks, had just got through reading the second link I found on my own, and another one I found when searching. All seems simple enough so will hopefully get a chance to play CPU-swapsies during the week and see if I can get this thing booting or not!

I feel like I'm putting in a lot more effort than it's worth but I'm not ready to give up on it yet ;-)
 
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amedias

macrumors regular
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Devon, UK
minor update!

Haven't had time to do CPU swapsies as the DA is actually chugging away doing something useful for now.

But I'm now almost convinced it's a logic board issue as I've tried to boot it from another mac in target disk mode and it doesn't find any disks.

Tried from one of my PowerBooks and nothing, tried the same PowerBook as target disk on the DA and that boots fine, so no issue with target disk mode on the PB, and cable confirmed good.

That leads me to conclude that the QS either has a definite logic board issue OR it *also* has dead FW ports as well as whatever else is going on, think I might cut my losses on this one and salvage the CPU and toss the board...
 

Raging Dufus

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minor update!

Haven't had time to do CPU swapsies as the DA is actually chugging away doing something useful for now.

But I'm now almost convinced it's a logic board issue as I've tried to boot it from another mac in target disk mode and it doesn't find any disks.

Tried from one of my PowerBooks and nothing, tried the same PowerBook as target disk on the DA and that boots fine, so no issue with target disk mode on the PB, and cable confirmed good.

That leads me to conclude that the QS either has a definite logic board issue OR it *also* has dead FW ports as well as whatever else is going on, think I might cut my losses on this one and salvage the CPU and toss the board...
Firewire issues are often a precursor to PSU failure. You've been pretty exhaustive in troubleshooting, so at this point I think you're down to a couple of possibilities: it's either the PSU or the logic board. Maybe even both, because sometimes a failing PSU messes up other components on its way out.

In any event, kudos! You've given it a first class try. If you're not willing to go any further down the rabbit hole, then give that old Quicksilver a salute and send it off to a well-deserved retirement.
 

amedias

macrumors regular
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Feb 9, 2008
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Devon, UK
Well I might give it one last go next week as I *think* I have a spare PSU so given how easy it will be to check it's got to be worth a try just in case.

If it is a lost cause then I'll salvage the CPU, toss the board and stash the case for either a mini-atx conversion or for spares in case someone needs handles/panels etc.
 
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