iMac

Did you know your iMac can double as a monitor for another Mac or PC? This feature, known as Target Display Mode (TDM), is a hidden gem in Apple’s ecosystem. While Apple has since discontinued support for TDM on newer iMacs, older models still offer this functionality, making them an excellent option for repurposing your iMac. Here’s everything you need to know about using your iMac as a second display.

Which iMacs Support Target Display Mode?

Not all iMacs can act as external monitors. TDM is supported on:
– iMac (27-inch, Late 2009 and Mid 2010): Requires macOS High Sierra or earlier.
– iMac (Mid 2011 to Mid 2014): Works with macOS Mojave or earlier.

Unfortunately, newer iMacs (2015 and later) and M1/M2-based Macs do not support this feature.

What You’ll Need

To set up Target Display Mode, ensure you have:
1. A compatible iMac (see list above).
2. A Mac or PC with a Mini DisplayPort or Thunderbolt port.
3. The correct cable:
– Mini DisplayPort to Mini DisplayPort or Thunderbolt to Thunderbolt cables for Mac-to-iMac connections.
– An adapter if connecting from a PC with HDMI or USB-C output.

How to Enable Target Display Mode

1. Connect the two devices using the appropriate cable.
2. Turn on both the iMac and the source device.
3. On the iMac, press Command (⌘) + F2 (or Command + Fn + F2 on some keyboards). This toggles the iMac into Target Display Mode.
4. Voilà! Your iMac should now display content from your other device.

Pro Tips and Limitations

• Resolution Cap: Your iMac will display at its native resolution, which might differ from your source device’s settings
• No TDM on macOS Ventura+: Due to compatibility issues, TDM won’t work on your source Mac running macOS Ventura or later.
• Audio Output: The iMac can also play audio from the connected device. To do this, tweak the sound settings on your source Mac or PC.

Alternatives for Newer Macs

If you’re using an M1/M2 Mac or a newer iMac, consider alternatives like Sidecar (to use an iPad as a second screen), Universal Control, or third-party apps like Luna Display for similar functionality.

Repurposing an older iMac as a monitor is cost-effective and eco-friendly—proving that even aging Apple tech can still shine in today’s workflows!

https://www.cultofmac.com/how-to/use-imac-as-monitor