View Full Version : Extra HD on dual 867 MDD shows up intermittently
Dec 26, 2004, 03:33 PM
I recently obtained a dual 867 G4 MDD with two additional hard drives (one on the front and one on the rear carrier). The one on the rear has a capacity of 186 GB while the one on the front has a capacity of 168 GB. The rear drive will always appear after the machine is turned on, but the drive on the front will occasionally appear. I have tried disconnecting and reconnecting the cables, but the problem still persists. I have noticed that the drive on the rear is an ATA drive and the drive on the front is an IDE drive, don't know a whole lot about the types of drives and any help would be greatly appreciated.
Also, I've had some difficulty with Target mode with this computer in either direction to my Ti G4 500 MHz. It appears that either HD is not recognized when in Target mode.... any ideas? Thanks.
Dec 26, 2004, 03:41 PM
I think technically all ATA drives are IDE drives.
I believe that the drives will be marker as 180GB capacity and 200GB capacity (marketing numbers versus engineering numbers).
If the drive doesn't always show up, the drive can be going bad, the cable can be flaky or the disk controller is bad.
I'd err on the side of caution and back up any data you need from that drive.
Dec 26, 2004, 04:00 PM
Thanks for the reply. I was thinking about switching the drives in the front and rear, but will the ATA66 vs. ATA133 (speed??) matter? I think that will solve whether or not it's a cable issue. What is a disk controller and more importantly, how expensive is that to replace?
Dec 26, 2004, 04:05 PM
I had a similiar problem with my secondary serial ata drive. It would only appear occasionally after the computer started up. One day, the computer froze while in itunes and upon reboot the drive was gone for good. The disk utility could still see the drive but the verify check failed on it. The drive had indeed gone bad.
Fortunately I was able to use a data recovery utility to get my stuff back.
If I were you I would back up you stuff as soon as possible, your drive could be going bad.
Dec 27, 2004, 09:28 AM
Thanks for the reply. I was thinking about switching the drives in the front and rear, but will the ATA66 vs. ATA133 (speed??) matter? I think that will solve whether or not it's a cable issue. What is a disk controller and more importantly, how expensive is that to replace?On the MDD models (as in most of the Powermacs) it requires a replacement of the logicboard. Another option is to put both disks on the same controller. Or you can buy a third party controller (for under $40) and stick it in a PCI slot.
Swapping the drives first is a good idea. And actually the 2 internal ATA controllers are ATA/100 and ATA/66 and with just one drive on each controller, you probably won't really notice much difference.
Dec 27, 2004, 10:11 AM
The ATA 100/66 connectors will only recognize up to 128 gigabytes so an ATA 133 controller must be used to connect either drive.
Now I have had problems with a drive showing up intermittantly and it turned out to be the controller which was at fault. I would most definetly attempt swapping the drives to ascertain whether or not the controller is at fault. If so you can run both drives on the same controller or through a PCI controller, as mentioned before.
Definetly do backup as I had a drive fail in another computer suddenly and unexpectantly. Always backup or you may regret it later.
Dec 27, 2004, 11:02 AM
Wrong!The ATA 100/66 connectors will only recognize up to 128 gigabytes so an ATA 133 controller must be used to connect either drive.
...ATA/IDE interfaces which have less than 48bit addressing (which has nothing to do with the speed) have the limitation. ATA/IDE interfaces which have 48-bit addressing do not have this issue. The MDD Powermacs have 48-bit addressing on all (including the one for the optical drive) of the built-in ATA/IDE controllers.
I also have an MDD system and I have multiple drives in it over 128GB with no issue.
Also, if you had read the original message in the thred, the person has a larger than 128GB drive in his system on the built-in controller and they can see the whole drive.
Know your system and don't parrot the incorrect information available on the net. Also, some of the later Quicksilver models apparently are okay for larger drives on the built-in IDE controllers.
It's true that all ATA/133 controllers do have 48-bit addressing. I'm not sure if all ATA/100 controllers have 48-bit addressing. And yes with an ATA/66 controller, you do have to know if it supports 48-bit addressing.