Re: Seeking Help with Failing Late 2013 27" iMac - Update

[imac_ben]

Hello,

Earlier this year I posted about a failing late 2013 27" iMac. The thread is here.

Thanks to the responses in that thread, we determined it was a failing fusion drive and I was able to get the machine booting to an external ssd. This has worked out very well and due to some very good luck, I was able to recover almost all of my important data before the fusion drive was completely inaccessible.

I now have a slight issue: When I boot up, before hearing the startup chime through the speakers, I hear a funny crackling/ screeching sound (not through the speakers). It varies from boot to boot. Sometimes it is louder, sometimes it is more subtle. I assume it is something to do with hardware, perhaps the machine trying to access the old dead/ dying fusion drive at the initial stages of boot-up. I shutdown the machine each night, so hearing this sound every morning is a bit alarming. Does it sound like something I should be concerned about?

On the same subject, I would like to erase and reformat the surviving ssd portion of the fusion drive. Is this as simple as erasing and reformatting it in disk utility or does it need to be severed from the hdd? I am confused about this because the hdd seems to still be lingering inside the machine. When I first started booting to the external ssd, the fusion drive was available in finder and I was able to slowly recover some remaining data from it. Now it does not show in finder and when I get booted up, I receive a dialogue saying a disk cannot be initialized with an option to initialize or eject it. i have just been ejecting it. In Disk Utilirty, the fusion ssd always shows up and the hdd sometimes shows up, though it reports varying storage capacities for the hdd. Likewise, DriveDX sometime shows it and sometimes does not. I have attached screenshots showing these reports.

I am hoping some of you guys on here can help shed some light on what I have going on. Is this crackling sound at boot something to be concerned about? Can I erase and reformat the fusion ssd to use as a storage drive? Is there any way to permanently disconnect the fusion hdd and leave it dead inside the machine?

Please let me know if you have any ideas. Your help is much appreciated.

Ben.

 

[Fishrrman]

"I now have a slight issue: When I boot up, before hearing the startup chime through the speakers, I hear a funny crackling/ screeching sound (not through the speakers). It varies from boot to boot. Sometimes it is louder, sometimes it is more subtle. I assume it is something to do with hardware"

When you "converted" to an external boot drive, you left the internal HDD and SSD in place, right?

If so, THAT'S what I think you're hearing. It's probably the internal platter-based hard drive making the sounds (either from platters that refuse to spin up or an actuating head that is having problems).

"On the same subject, I would like to erase and reformat the surviving ssd portion of the fusion drive. Is this as simple as erasing and reformatting it in disk utility or does it need to be severed from the hdd?"

Yes.
Absolutely.
Just erase it using disk utility as you would erase any other drive.
It should give you a 128gb SSD -- quite fast, as well.

I would then install a copy of the OS onto it, put some apps on it, put an account onto it, and just "keep it there" as an alternate boot drive. It may actually run considerably faster than your external boot SSD.

And while you're at it:
IF the platter based HDD will respond to disk utility, I suggest you erase that, too.
Then, just "leave it there, unused".
If it has problems spinning up, you may not be able to do this. Again, "just leave it there".
Work around it, and keep the iMac going.

As I mentioned in my earlier postings to you in the earlier thread:
Don't over-think these things.
Just DO THEM.

 

[imac_ben]

Hey Fishrrman. Thank you for the response.

Indeed, I did not open up the iMac when I converted to the external boot drive. So yeah, the old drives are still sitting in place.

I just erased and reformatted the ssd without any issues. Glad to have that available as a drive now. I am going to try setting it up as an alternative boot drive as you suggest and see how it runs. Perhaps I will set it up with bootcamp as you suggested in my other thread so I can get windows back on this machine too.

The internal hdd was available in disk utility today, but it did not respond to my attempt to erase and reformat. I will just leave it there lime you said.

Thanks again for your help and encouragement. I definitely tend to overthink these things, but I am learning. The knowledge base and expertise on this forum is much appreciated.

Ben.