Three Drives showing on my iMac

[Jimbo Asprilla]

*UPDATED*
My 2019 21.5" iMac is showing 3 system drives (see attached pic) the machine has been running like garbage since I got it (certified Geek Squad refurb from Best Buy) I'm constantly getting warnings that I'm running out of storage space.

Any recommendations?

TLDR

As recommended I installed Catalina on an external SSD, OMG wow all my speed issues have gone.

 

[Taz Mangus]

It looks like your install is messed up. I would suggest you do a backup of your system and then do a clean install of 10.15.6. Or you might want to consider returning the computer if you are within your return period.

 

[Jimbo Asprilla]

It looks like your install is messed up. I would suggest you do a backup of your system and then do a clean install of 10.15.6. Or you might want to consider returning the computer if you are within your return period.

should I delete/remove any of these extra drives first?

 

[Taz Mangus]

should I delete/remove any of these extra drives first?

No. Boot into Recovery Mode (Command (⌘)-R), erase the physical drive and reinstall the latest 10.15.6 Catalina.

Use Disk Utility to erase an Intel-based Mac - Apple Support

How to erase (format) the built-in startup disk of an Intel-based Mac.

support.apple.com

How to reinstall macOS - Apple Support

You can use macOS Recovery, your computer's built-in recovery system, to reinstall the Mac operating system. Reinstalling macOS doesn't remove your personal data.

support.apple.com

 

[Analog Kid]

No. Boot into Recovery Mode (Command (⌘)-R), erase the physical drive and reinstall the latest 10.15.6 Catalina.

I think it was implicit, but do this after backing up. (I'm not sure if the OPs question was whether they should delete drives before backing up).

 

[Jimbo Asprilla]

I think it was implicit, but do this after backing up. (I'm not sure if the OPs question was whether they should delete drives before backing up).

yes, in fact I’ve barely got anything on the machine, I’ve wiped the system a couple of times since I got it due to desperation of how bad it’s been running.

 

[glenthompson]

With the spinning drive it’s going to run like crap. You really need a SSD. Consider an external SSD to boot from and hold applications.

 

[Fishrrman]

Jimbo:

Try this.
WARNING: doing this will erase everything on the drive, so save anything you want to save to a backup before going further.

1. Boot to a special version of internet recovery:
shift option command R
(you'll need your wifi password if you're not connected to ethernet)

2. When the internet utilities load (it takes a while), open disk utility

3. Go to the "view" menu and choose "show all devices" (IMPORTANT step)

4. Now look at the left. You want to choose the topmost line, this represents the physical drive inside.

5. Click on it to select it, then click ERASE. Choose APFS with GUID partition format.

6. Once the drive is erased, open the OS installer and try again.

How does this work out for you?

 

[Jimbo Asprilla]

Jimbo:

Try this.
WARNING: doing this will erase everything on the drive, so save anything you want to save to a backup before going further.

1. Boot to a special version of internet recovery:
shift option command R
(you'll need your wifi password if you're not connected to ethernet)

2. When the internet utilities load (it takes a while), open disk utility

3. Go to the "view" menu and choose "show all devices" (IMPORTANT step)

4. Now look at the left. You want to choose the topmost line, this represents the physical drive inside.

5. Click on it to select it, then click ERASE. Choose APFS with GUID partition format.

6. Once the drive is erased, open the OS installer and try again.

How does this work out for you?

I did this and I’m now stuck in recovery mode, when my Mac does it’s first reboot during installation, instead of booting in to the clean install, it reboots back in to the recovery mode.

i’ve now gone through this cycle about 4 times tonight.

 

[Taz Mangus]

Do you have access to another Mac computer. If you do you can download the Catalina installer from the Mac App Store and create a bootable USB installer. Boot to the installer and install Catalina to your 2019 21.5” iMac.

One thing that was not clear was if you were erasing the physical drive or Macintosh HD. If you erase Macintosh HD you will end up with multiple instances of Macintosh HD - Data.

Create a bootable installer for macOS - Apple Support

You can use a USB flash drive or other secondary volume as a startup disk from which to install the Mac operating system. These steps are primarily for system administrators and other experienced users who are familiar with entering commands in Terminal.

support.apple.com

 

[Jimbo Asprilla]

Do you have access to another Mac computer. If you do you can download the Catalina installer from the Mac App Store and create a bootable USB installer. Boot to the installer and install Catalina to your 2019 21.5” iMac.

One thing that was not clear was if you were erasing the physical drive or Macintosh HD. If you erase Macintosh HD you will end up with multiple instances of Macintosh HD - Data.

Create a bootable installer for macOS - Apple Support

You can use a USB flash drive or other secondary volume as a startup disk from which to install the Mac operating system. These steps are primarily for system administrators and other experienced users who are familiar with entering commands in Terminal.

support.apple.com

WOW, did as you recommended and installed Catalina via USB to my external SSD, WOW ! all my performance problems are gone ! what a huge difference ! thank you for your advice and everyone who replied.

 

[Taz Mangus]

WOW, did as you recommended and installed Catalina via USB to my external SSD, WOW ! all my performance problems are gone ! what a huge difference ! thank you for your advice and everyone who replied.

Glad it worked out for you.