iMac (21.5“ Late 2103) as monitor for Windows 11 laptop

Tom_84 wrote:

Hi!

I have an IMac (21.5", Late 2013 with MacOS 10.13.6 installed) and want to use this as a monitor for my laptop (DragonFly with Windows 11 installed).

I don't think that's going to work. That iMac supports Target Display Mode – but it requires Thunderbolt input, and Apple has also added a restriction that the other machine must be a Mac released in 2019 or earlier that is running Catalina or earlier.

Use your iMac as a display with target display mode - Apple Support

For my laptop, i have a port station with DisplayPort connections for monitors. I have bought a connection cable from DisplayPort to Thunderbolt 2.

I don't know whether you bought a DisplayPort cable – or an old-style Thunderbolt one that has Mini DisplayPort connectors on the ends. Either way, it's not going to work. All of the iMacs that supported Target Display Mode, and that also had Thunderbolt ports, required Thunderbolt input. You're supplying DisplayPort input.

I have connected the cable to the IMac and also to the port station of the laptop and have pressed cmd+F2 (I have activated the F1+F2 keys in the system). Unfortunately it was not working. I have also tried to connect the IMac via the connection cable from Thunderbolt via an adapter (DisplayPort to USB-C) directly to the laptop and pressed again cmd+F2. Also not working.

Same reasons: (1) that iMac requires Thunderbolt input, and you're supplying DisplayPort input, and (2) Apple added restrictions such that your DragonFly laptop is not a supported video source for using an iMac with TDM.

Den.Thed is 100% correct, iMacs are computers, they are NOT external displays for other devices. If your PC needs an external display, please buy one. Why??

• Dead Reliable
• Does not require expensive cables
• Simple setup
• In-expensive (less than $100 for many external displays)

Tom_84 wrote:

Any ideas what could be the reason, why i cannot use the IMac as a Monitor?

Because the iMac is an all-in-one computer, not a display for other computers.