Quicksilver G4 ATA Bus Problems

[andrewgurn]

I have a strange issue with a Quicksilver G4, and I am wondering if any of you guys might have some insight.

I can only boot from an HDD when it is attached to the ATA bus that is usually used for the optical drive. When a drive is plugged into the other bus (the one near where the HDD is supposed to mounted), the disk is recognized as a start up disk, but booting results in I/O errors when OS X (using verbose mode) starts trying to load files (OS 9 doesn't boot either; you just get the "disk ?" icon). But the weird thing is, I can boot to the disk fine when it is on that bus using another Mac and the Quicksilver is in Target Disk mode.

I've tried several different HDDs, including a SATA SSD+adapter, in several different master/slave/cable select configurations, reset the PRAM, put in a fresh battery... even swapped the logic board and CPU (as I was troubleshooting this issue, the QS stopped booting entirely, so I had to do some shopping on usedmac).

When I put an optical drive on the faster bus, I can boot from installation CDs with no issues.

Anyone run into something like this before? It's driving me a little crazy at the moment.

 

[andrewgurn]

Wait, huge development: I am possibly just an idiot

Which bus is the boot drive intended to be attached to? The one one near the Airport card, or the one near the PCI slots?

When I bought this thing, there was drive mounted to the bottom of the case on a plate and attached to the bus near the PCI slots. I assumed this was correct. I just removed the metal holder that has the optical drive in it and realized that the slot below it fits a 3.5in HDD perfectly... almost as if intended

 

[Coloruser]

The Quicksilver has one Ultra-ATA and one IDE connector. See attached image..….connect your HD to the Ultra-ATA for optimal speed.

 

[andrewgurn]

OK, so I was right the first time: My Ultra ATA connector is the one that causes problems when there is a disk attached to it. I/O errors, errors when formatting from disk utility, etc

 

[Coloruser]

Are you using an IDE cable or dedicated Ultra-ATA cable?

 

[andrewgurn]

Are you using an IDE cable or dedicated Ultra-ATA cable?

Ah. I'm using the cable that came with it when I bought it (used, not new). It sure looks like a regular IDE cable. I did not know that Ultra-ATA cables were a thing. I see about acquiring one of those now that I know they exist

 

[Coloruser]

UDMA cables have 80 wires (vs. 40 for IDE). However, the connector is still 40pin. Only with such a cable, the drive and controller can work out the right protocol and speed.

 

[andrewgurn]

Yep, a proper cable fixed all issues. I learned two things here; 1) not all IDE cables are the same, and 2) I should never assume the last guy who had owned a Mac I bought had any more idea of what he was doing than I do, haha

Although I am still confused that having the disk plugged into the Utra-ATA port with a regular IDE cable had no issues when being used in Target Disk mode

 

[Coloruser]

Maybe in target disk mode, the drive is accessed with a slower PIO or less critical UDMA33 protocol. That would at least explains it. FireWire 400 (i guess that was used for target disk mode) has a theoretical speed limit of 50mb/sec but there are many reports that it is capped at around 30mb/sec in target mode.