Remove Apple ID and upgrade older iMac

Need to know how to use an older iMac's monitor as a second one for my Mac Studio.


Posted on Jul 11, 2026 1:19 PM

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Question marked as Top-ranking reply

Posted on Jul 23, 2026 3:59 PM

Hi,

As remove AppleID and upgrade older iMac:


To remove an Apple ID and upgrade an older iMac, sign out via System Settings/Preferences, install official OS updates, and replace slow mechanical hard drives with an SSD. [1234]

Removing an Apple ID

  • Open System Settings (or System Preferences on older macOS) from the Apple menu.
  • Click your name or Apple Account / Apple ID at the top of the window.
  • Scroll down and click Sign Out.
  • Choose whether to keep a local copy of your data, then enter your Apple ID password to turn off Find My Mac and clear activation locks.

Upgrading Software and Hardware

  • Official Software Updates: Go to the Apple menu > System Settings (or System Preferences) > General > Software Update to install the highest version officially supported by Apple for your specific iMac model.
  • Storage and Memory: Speed up performance drastically by swapping an old internal hard drive for a solid-state drive (SSD), and add more RAM if your specific iMac model allows memory modules to be replaced.

If you share the exact year and model number of your iMac, I can tell you:

  • The highest official macOS version it supports
  • Whether you can upgrade the RAM or hard drive yourself


  • What to do before you sell, give away, trade in or recycle your ...
  • 2026/02/04 — macOS Ventura 13 or later: From the Apple menu , choose Sys...
  • Apple Support
  • Remove Apple ID and upgrade older iMac
  • 2026/07/12 — Remove Apple ID and upgrade older iMac. Need to know how to ...
  • Apple Support Community.


As for Need to know how to use an older iMac's monitor as a second one for my Mac Studio.

You need to get Thunderbolt or FireWire(depend on your iMac has) to USB-3 adapter for Target Display Mode, though it could not work, since Target Display Mode is old technology.


2 replies
Question marked as Top-ranking reply

Jul 23, 2026 3:59 PM in response to nachistbuff

Hi,

As remove AppleID and upgrade older iMac:


To remove an Apple ID and upgrade an older iMac, sign out via System Settings/Preferences, install official OS updates, and replace slow mechanical hard drives with an SSD. [1234]

Removing an Apple ID

  • Open System Settings (or System Preferences on older macOS) from the Apple menu.
  • Click your name or Apple Account / Apple ID at the top of the window.
  • Scroll down and click Sign Out.
  • Choose whether to keep a local copy of your data, then enter your Apple ID password to turn off Find My Mac and clear activation locks.

Upgrading Software and Hardware

  • Official Software Updates: Go to the Apple menu > System Settings (or System Preferences) > General > Software Update to install the highest version officially supported by Apple for your specific iMac model.
  • Storage and Memory: Speed up performance drastically by swapping an old internal hard drive for a solid-state drive (SSD), and add more RAM if your specific iMac model allows memory modules to be replaced.

If you share the exact year and model number of your iMac, I can tell you:

  • The highest official macOS version it supports
  • Whether you can upgrade the RAM or hard drive yourself


  • What to do before you sell, give away, trade in or recycle your ...
  • 2026/02/04 — macOS Ventura 13 or later: From the Apple menu , choose Sys...
  • Apple Support
  • Remove Apple ID and upgrade older iMac
  • 2026/07/12 — Remove Apple ID and upgrade older iMac. Need to know how to ...
  • Apple Support Community.


As for Need to know how to use an older iMac's monitor as a second one for my Mac Studio.

You need to get Thunderbolt or FireWire(depend on your iMac has) to USB-3 adapter for Target Display Mode, though it could not work, since Target Display Mode is old technology.


Jul 12, 2026 10:36 AM in response to nachistbuff

nachistbuff wrote:
Need to know how to use an older iMac's monitor as a second one for my Mac Studio.


Please don't hijack other people's threads.


If you are referring to Target Display Mode, note that Apple retroactively added restrictions to it. Now the video source has to be a Mac released in 2019 or earlier, running Catalina or earlier. Which rules out all Mac Studios.

Remove Apple ID and upgrade older iMac

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