
I built an open-source way to use a 5K iMac as a display without gutting it
I have a 2017 27-inch 5K iMac that I still really like, but I wanted to use it as a display for my M3 Pro MacBook.
The usual solution is to open the iMac, remove the logic board and install a third-party display controller. That works, but I really didn’t want to gut a perfectly functional machine just to keep using the panel.
So I ended up building monitorOS: github.com/eriskhan/monitorOS
It boots Linux on the iMac and turns it into a dedicated display appliance.
At this point I have:
- 5K / HiDPI
- Display P3
- native macOS brightness controls
- audio through the iMac speakers
- automatic discovery and connection
- low-latency transport
- one Thunderbolt cable between the Mac and iMac
The iMac stays intact - original logic board, GPU, display, speakers, everything.
It’s still an early release, and right now my tested setup is a 2017 5K iMac with Radeon Pro 580 + M3 Pro MacBook Pro, so I’d especially love to hear from anyone with other Radeon Pro iMacs who wants to try it.
Would love feedback, especially from anyone who has one of these iMacs sitting around unused.