What impact would a bad IDE cable have?

[sequencers.io]

I've been trying to track down what's causing the random system freezes & intermittent boot failures on my accelerated G4 DA, and a possible candidate at this point is the IDE cable leading to the CD-ROM. There is a significant kink in the ribbon between the two IDE connectors; some of the wires seem quite bent, some are exposed, and although I cannot see any outright breaks, I fear that perhaps one of the wires in the ribbon has been broken, leading to impaired impedance in data wires/broken ground wires.

I've tried to research what sort of impact a faulty IDE cable on the "secondary" IDE bus (not sure of the nomenclature here) could have - data corruption & failed reads from optical media are common conclusions. However, it seems hard to imagine this might be causing freezes and lock-ups when not using the optical drive. Maybe polling that IDE bus causes issues?

[IIO]

if you dont use a number a externals drives or do something in a burning software there should not be so much happening at that port i think. especially since it is on its own bus and not releated to the HD(s)

have you tried yet to remove the cable for a few weeks and see what happens?

[macarone]

This has been well answered, but I can't resist adding that using two optical drives on an IDE cable in master/slave configuration is NOT recommended.

Any serious MDD owner that wanted to add a second optical drive, also added a PCI card to add SCSI, IDE or later SATA ports.

[sequencers.io]

I'm not using two optical drives. Just one. I haven't tried disconnecting the bus yet as I've been trying to use AHT to diagnose my issues, but perhaps will have to try a different cable to get it to run (when I can get it to boot, it usually just hangs, and not sure if that's a result of the ribbon, my burn effort or the system).

[GaryN]

I've been trying to track down what's causing the random system freezes & intermittent boot failures on my accelerated G4 DA,

I submit that THIS is by far the most likely culprit for symptoms of "freezes & intermittent boot failures".
I understand (and sympathize) that you would really rather it be a simple bad cable, but realistically…

There was an old story, sometimes told in cartoon form where Joe sees Ed across the street looking around under a streetlight.
He yells, "Whacha doin', Ed?" Ed says, "Looking for my wallet. I dropped it over there"
Joe says, "If you dropped it over here, why are you looking over there?"
Ed says, "The light's better over here."

[sequencers.io]

I submit that THIS is by far the most likely culprit for symptoms of "freezes & intermittent boot failures".
I understand (and sympathize) that you would really rather it be a simple bad cable, but realistically…

When I bought this machine, I realized it might have any number of possible hardware issues. Given I bought it with the accelerator installed, I don't really have a previous state to compare it to. The previous owner - who primarily ran OSX on it - said it was very stable for them. It also seems quite stable under OSX, with no random freezes that I've experienced, and I've left it up and running for days. I only get random freezes when it is booted into OS9. Boot failures have - more often than not - occurred when I was trying to boot from optical media.

[GaryN]

Without knowing which accelerator we're talking about, it's difficult or impossible to offer any better advice.
I will note that most, if not all 3rd-party CPU's require an extension to be loaded in ≤OS 9 that is not required in OSX.
That could explain the boot-from-optical issues if that System does not contain the Extension.
The next question is of course, why are you booting from disc? When you install an OS on the HDD, you then get to adjust and modify it to run it's best on your machine… but you already know that.

More info will produce better results.

[sequencers.io]

It's a Sonnet Encore/ST G4 (Part #SG4-1400-2M), which from what I've read, only requires a firmware patch, which it seems like it has, since it is booting... if there's an extension I can drop in the System Folder lmk what I've missed in my research!. FWIW, it has:

ROM Revision: $77D.45F6
Boot ROM Version: $0004.28f1

I'm booting into both the MacOS9Lives & Instant DAW distributions. I've been booting from optical media when I was installing different versions of OSX, when I couldn't seem to boot off OS9 from my hard drives, and when I would experience multiple frequent hangs of a fully-booted OS9. I also booted from optical media (or tried to) while going through 3 bad/incompatible video cards in a row (the 9800 it shipped with, and 2 Radeon 9000s) as I found the installer - when it would boot - would give me a useable video signal more reliably than when booting from hard drive, so bottom-line, the boots from optical were for debugging.

I recently replaced the battery on the mainboard, as it wasn't retaining date/time when power was disconnected, but that behavior persists so starting to seem like a mainboard issue. If I can get the AHT to run, maybe I could say for certain.

[GaryN]

Many things to address here…

Your firmware $0004.28f1   is correct.
AHT will not run with a 3rd party CPU

I have a 2x1.8GHz Sonnet Encore/MDX Duet in my MDD, so I do know a few things about this.
There absolutely IS a Sonnet Crescendo Extension to be installed in the OS9 Extensions Folder. It's gimmicked to load first or second.
It's installed from the Sonnet CD ROM.  When it's present, as soon as it loads, you see a modified boot screen similar to Pic 1 below.
I have no idea how or where to find the exact one for your ST if you don't have that CD ROM.
I'm thinking you do NOT have the ST Duet dual-proc version. If by some chance you do, there is also a replacement "Apple CPU Plugins" file that goes in the "Multiprocessing" Folder. AFAIK though, the computer won't run at all in OS9 without that file so you must have the single CPU.

I'm attaching a copy of my Sonnet extension. You'll need Stuffit Expander to restore it.
I have absolutely no idea if it will work with your ST.  BUT, it probably can't hurt either so you can at least try it.
Just drop it into the Extensions Folder, cross your fingers and reboot into OS9. If everything goes South, you can reboot in OSX and remove it.

Good luck.

[sequencers.io]

Yeah, it's a single. Thanks for the extension. I'll see what it does. I don't have the original CPU (or the installer media). If the extension doesn't improve reliability, there's a local vintage Apple dealer here in Colorado with a G4 DA mainboard (and original Apple IDE cable for the optical drive) so I might consider swapping them out - or I might just keep my eye open for another G4.

I thought I had read somewhere that a failure to keep date & time after replacing the battery was a warning sign of a bad or failing mainboard. Good to know AHT won't run, so I can stop wasting my time trying to get it to do so.