Mac OS Ventura TARGET DISPLAY MODE IS BACK!! Using an old iMac as a monitor OCLP

Summary

In this update video, the creator demonstrates using Target Display Mode on older iMacs running unsupported macOS versions via OpenCore Legacy Patcher. They showcase a late 2013 iMac on Ventura and a late 2012 iMac on Monterey, highlighting seamless functionality with both Mac and Windows keyboards. The video covers setup, troubleshooting, and performance, including zero-lag display, hotkey usage, and resolution adjustments. The creator also discusses compatibility issues, forward compatibility quirks, and cost-effective alternatives to modern displays. Viewers gain practical guidance for reviving older iMacs as secondary monitors, making it a useful resource for tech enthusiasts looking to extend the life of legacy hardware.

Takeaways

• 💻 The video demonstrates using Target Display Mode on older iMacs, specifically a late 2013 27-inch running Ventura and a late 2012 27-inch running Monterey.
• ⚡ Both iMacs are unsupported Macs running newer operating systems via OpenCore Legacy Patcher to enable installation of newer macOS versions.
• 🖥️ Target Display Mode works with both Mac and Windows keyboards, including wireless keyboards, using the Command + F2 hotkey.
• 🔗 The two iMacs are connected via a Thunderbolt-to-Thunderbolt cable, providing a lag-free display experience.
• 🖨️ The older iMac running Monterey allows sharing of a printer to the Ventura system, compensating for lack of official drivers.
• 🚨 Upgrading macOS via OpenCore Legacy Patcher can cause issues such as boot loops if post-install patches are not applied correctly.
• ✅ Target Display Mode works across two different macOS versions (forward compatibility from older to newer OS), though reverse compatibility may cause graphical issues.
• 📦 Budget-friendly solution: Both iMacs were purchased on eBay for around $700 combined, providing two 27-inch monitors as a cost-effective alternative to a Studio Display.
• 🔧 Ventura’s system settings are different from older macOS versions, but the new setup runs smoothly with zero lag on Target Display Mode.
• 📌 Not all iMac models support Target Display Mode; Retina iMacs (2015 and newer) do not support it. Check Apple’s website for compatibility before attempting.

Q & A

What operating systems are being used on the two iMacs in the video?

The late 2013 27-inch iMac is running macOS Ventura, while the late 2012 27-inch iMac is running macOS Monterey.

What tool is used to install unsupported software on these older iMacs?

The OpenCore Legacy Patcher is used to install unsupported software on the older iMacs.

How does the presenter demonstrate Target Display Mode?

The presenter shows Target Display Mode by using the hotkey Command + F2 to turn one iMac into an external display for the other iMac.

Can Target Display Mode work with wireless keyboards?

Yes, the video confirms that Target Display Mode works with both wireless Mac and Windows keyboards.

What is the connection method used between the two iMacs?

The iMacs are connected using a Thunderbolt-to-Thunderbolt cable.

What issue did the presenter encounter when using the OpenCore Legacy Patcher?

The presenter experienced a boot loop after reinstalling post-install root patches, which required upgrading one iMac to macOS Ventura.

Is Target Display Mode forward compatible between older and newer macOS versions?

Forward compatibility is limited. The presenter initially experienced graphical issues when attempting to target display from Monterey to Ventura, but after reseating the Thunderbolt cable, it worked properly.

Why is the older iMac kept on macOS Monterey?

The older iMac is kept on Monterey to maintain compatibility with a printer for which drivers are not available on Ventura.

What budget considerations does the presenter mention for acquiring two iMacs?

The presenter acquired the iMacs on eBay for approximately $400 and $300, totaling around $700 for two 27-inch monitors, which is a budget-friendly alternative to buying a new studio display.

Which iMac models do not support Target Display Mode?

Retina iMacs, starting from around the 2015 model, do not support Target Display Mode. The presenter advises checking Apple's website for specific compatibility.

How does the presenter manage printer sharing between the two macOS versions?

Since the printer is incompatible with Ventura, the presenter shares the printer over the network from the Monterey iMac so Ventura can access it.

What advantage does Target Display Mode provide over software solutions like Air Display?

Target Display Mode offers a native, zero-lag external display experience, which works more reliably than software solutions like Air Display.