use iMac 27" as external display for MacBook Pro 2023?
I'm purchasing a new MacBook Pro 2023. Will I be able to use my old iMac 27" 2015 as external display?
iMac 27″, macOS 12.7
Question marked as
The very restrictive hardware and system software requirements for what you seek to do, Target Display Mode (TDM), are laid out in this Apple article:
Use your iMac as a display with target display mode - Apple Support
Both your Macs are too new both in hardware and OS versions to work via TDM. There may be third-party solutions but, like Apple's Airplay to Mac or network screen sharing, almost all are laggy. If you don't mind a delay between clicking and a result, lag may not be a problem for you.
The best solution is a regular external monitor. The cost of the cabling and adapters you'd need for TDM if even supported can nearly equal that of a decent monitor. An external monitor is also easier to connect, won't lag, offers full display options, and uses less power than a running iMac.
Apple began the deprecation of TDM in Late 2014 and threw the last shovel of dirt in its face almost four years ago.
