Using Your Old Cinema HD Display with a New iMac

If you're planning to purchase a new iMac and wish to use your old Cinema HD display monitor from your old Mac Pro as a second monitor, this guide will help you through the process. Understanding the intricacies of this setup can ensure a smooth and hassle-free experience for you.

Introduction to Target Display Mode (TDM)

One of the methods to achieve this setup is through Target Display Mode (TDM). This feature allows you to connect the two Mac computers, and use the display of one as an external monitor for the other. However, it's important to note that TDM is no longer supported across all iMac models, particularly starting from the late 2015 iMac. Therefore, ensuring compatibility is crucial in your decision-making process.

Scope and Conditions

To utilize Target Display Mode effectively, your old Cinema HD display must have a Thunderbolt connector. If it doesn't, you might face challenges in finding the necessary adapter. Additionally, the type of Cinema HD display you have plays a role in determining the appropriate adapter type.

Here are the key steps for setting up your old Cinema HD display with your new iMac:

Connecting Your Cinema HD Display

If your Cinema HD display has a Thunderbolt connector, connecting it to your new iMac will require an adapter. The adapter you need is the Apple Thunderbolt 3 USB-C to Thunderbolt 2 Adapter. This will enable the Thunderbolt functionality necessary to connect your display.

However, if your Cinema HD display has a mini DisplayPort connector, you'll need a USB-C to mini-DisplayPort adapter. This will allow you to connect your display to your new iMac. Both processes involve plugging the USB-C end of the adapter into the computer and the cable from the external display into the other end of the adapter. Once connected, your iMac should automatically recognize the display and allow you to use it as a secondary monitor. For further configuration, you can go to System Preferences > Display to specify the position of the additional display (left or right).

Limitations and Considerations

It's important to acknowledge that this setup will not be available with your new iMac in the future. Apple removed the ability for an iMac to operate as a secondary display starting with the late 2015 iMac. This means that if you want to continue using this setup, you should capture the process while it's still possible.

Conclusion

By following the steps outlined above, you can successfully connect your old Cinema HD display to your new iMac, enhancing your workspace and productivity. Remember to check the connectors and find the appropriate adapter to ensure compatibility. If you need further assistance, Apple's official documentation and support forums can provide additional guidance.