Internal Drives Randomly don't mount

[etnad]

HI all

My Machine;
Model Identifier: MacPro4,1 (Nehalem).Quad-Core Intel Xeon, 3,32 GHz,Number Of Processors: 1, Total Number Of Cores: 4, Memory: 8 GB


I added 3 drives to my Mac in the 3 empty drivew slots available in my configuration.

Once booting, one of them RANDOMLY does not mount.

I have a Western DIgital Original with 10.6.8 System in it which came with the Machine. I never wanted nor attempted to initialize it.
I purchased
disk A (Western DIgital 1TB)
disk B (Western DIgital 2TB)
disk C (Western DIgital 2TB)
All drives initiaiized with GUID, each of them with one partition.


Not mounting RANDOMLY means at times (along with the HD with the 10.6.8 system)
the Mac mounts disk Disk B and Disk C
other times mounts disks A and disk C
other times mounts disks A and disk B

I not able to reproduce the error, as I tried to simply boot without running any application. Besides the additional drives only contain photos or films and a few text documents. There are no system folders in any of them.

This suggest that the capacity of the disk is irrelevant.

Each drive functions perfectly according to every available tests, Systm Profiler, Disk Warrior and othe Utilities

They all display Make, Model, capacity and free space.

To perform the test I remove one drive at the time so the machine has only 3 drives to mount.The drives mounted quickly and go through the Verify disk and Replace Directory (in DISK WORRIOR)without any problem.
After swtiching off I move the drives arounf in the 4 slots to get same succesuful result.

I repeated the test with every drive in every slot.

I also instlled each drive in every of the four available slots in my MACPRO to make sure each slot hardware they worked

Every time rebooting the Mac with 3 Hard Drives in any of the slots was succesful
Every time I attempr rebootimg with 4 drives (one in every slot) the Mac only Mounts 3 drives.

[ColdCase]

Could the power supply have become lazy and has trouble spinning up four drives? If one SATA drive is slow, it won't get detected during boot and won't mount. If you put one drive in an external case do they all mount? Do you have high power Video card(s) installed?

A corrupted system has been know to cause unusual disk behavior. Dunno if what you are seeing is one of those. Have you repaired permissions on each disk?

If for some reason, the OS is set to max out at 3 SATA drives, the first two to be detected will mount, the last one will not. Drives have somewhat random startup timing so the specific drives that mount can vary.

[etnad]

Thanks for your reply ....
Yes all these drivesoriginally were in boxes and I moved them to become internal.
While in the box none had problems, and mount properly,

I don't understqanad though... tiy mention for the OS to be set to a mximum hard drives, i am not sure I understood properly, but it sounds as the most logical reason for my problem.

Is there a way to find out how to deal with this OS problem?Is it some parts within the hardware of my machine, or something I could deal with with Terminal although I am not at all experienced with it?

Regards from Italy

[ColdCase]

Someone else may jump in here, but I think conventional wisdom, when you suspect an OS problem, is to do a clean install and migrate.

I had SATA drive recognition issues when my 3,1 video card started to fail, perhaps because of the added power loading or interference. I ran through numerous troubleshooting steps, drive swaps, and hair pulls before the tell tale video coruption started to show up near two months later.

Which video card do you have?

[etnad]

ùMy Card is ATI Radeon HD 4870 and even trying all kind of different booting systems (v,s,x,ecc) nothing changed

If for some reason, the OS is set to max out at 3 SATA drives, the first two to be detected will mount, the last one will not.

How can I find out about how many Drives my OS allows to mount?

[Loa]

Originally Posted by etnad

How can I find out about how many Drives my OS allows to mount?

Are you running anything else than Mac OS X? If so, that's a crucial information to give. If you're running any flavor of OS X, you are able to mount a LOT more than 3 drives. I have 6 inside my 2009 MP, and 5 outside. No problem at all.

Can you mount the missing drive after the Mac is running?

Loa

[etnad]

I only have Mac OSX 10.6.8. indeed I can mount several different External drives, however the one I cannot mount is an Internal Drive (no matter which brand, I have WD, SeaGate in various Sizes).
However in my machine it looks as if only 3 can mount at any given time.
I tested each single slot, with only one HD at the time to make sure each drive and each slot was working.
Each Slot and each drive works, although I had to boot from the DVD for the ones without system folder and for precaution I used the latest version of DiskWarrior Bootable DVD and rebuild the various directories.
Everything works well if my Interneal Drives are up to 3.

Also with 3 Internal Drives I can also mount several additional external drives, but this does not count as they all hace their own external power source.

When I put the fourth HD and attempt to boot I only get 3 Drives.
As only one has a system folders, out of the remaining 3, the machine only mounts 3 but RANDOMLY. In other words is if is not capable to power them all.

Randomly means that each time the Internal Disk not mounting is never the same

IF A is my sistem disk, B the second and so on, I boot at times. ABC at others ACD at others ABD at others ABD.
There is no logic in this. I cannot reproduce how and why one disk is excluded from the booting process.
Their direcories where optimized with Disk Warrior in a very short time, and they are very large files (films, large NEF or TIFF ) pictures in RAW format,

At this point I believe I have a Power problem, and the reason why one disk does not mount is because the Machine will load the drive with the simplest directory (maybe less number of files or something like this) and eventually times out loading the fourth.

But this is only a guess as this "error" or whatever else I can call it does not happen in the same way, with the same drive and or the same slot.

It soulds wierd, as my local Apple Store couldn't find any faulty elements in the mother board and according to them the Poer System responds positively to their test.

In other words ... I am stuck. I even tried to put a very small sata inside but nothing changed.

Regards and thanks it feels as if either my Apple Shop center does not have the tools to find a mother board problems or the ghost of Bill Gates entered my machine and mocks me (I'm only joking)

Dan

[Loa]

Hello,

Unless I missed it in your answer I'll ask again: can you mount the missing volume after boot? (Manually, using Disk Utility.)

Loa

[etnad]

Sorry ni I can't boot it,
It appears in Sys Profiler with the code and alll the rest but not in Disk Utilities or any other appication dealing with Hard Drive problems

[Loa]

Hello,

Do you have any problems with your optical drive?

Also, can you unplug the optical drive and see what happens?

Loa

[etnad]

No problems there ... Everything seems to work fine, however tha machine gets slower and slower... still I can only see 3 drives, and up to 6 external Firewire and USB drives all at once. They appear in SYS Profile, and every other related software
The non mounting disk appears in SystemProfiles only but returns no "mount POint".
If I put it in a USB contanier it Mounts... Doing this test however I still fill up all the slots so the machine is chargerd with 4 internal drives.
Everything is Guid Prtitioned.
Is there any software able to check thouruoghly the mother board?
Gogle gives me no infos

[Loa]

Hello,

There are tools to check your hardware, but as far as I know you can't legally get them. They're called Apple Service Diagnostics, and you have to get the specific version for your mac model. This is the software that Apple uses for thourough diagnostics.

in the meantime, try this in your mac: turn it off, unplug your optical drive and boot with 4 drives in it.

Loa

[ColdCase]

After you try that, if you have access to another video card, swap it out and see what happens.

Do you have any other PCI slots filled with cards? If you do you may want to remove them and see what happens.

[AppleNewton]

I'd recommend reformatting the drives.

Also, are there any jumpers on the pins of the drive? This could be causing some of the issues you may be experiencing as well.