Rebooting an Apple Developer Transition Kit

In late 2020 Apple made a big shift, switching from the tried-and-true Intel processors that they had been using for years to their own silicon design with the M1 chips. This transition was more than just a fresh coat of paint. These new processors were Arm-based, which meant that software developed for Intel CPUs would not directly run on them. And naturally, that meant a lot of work for software engineers that wanted their applications to run on Apple’s latest computers.

To ease this initial transition, Apple released hardware called Developer Transition Kits. These boards came equipped with the new silicon designs, allowing developers to have a platform on which to build and test their software. These kits were all supposed to be returned to Apple after a period of six months or so, after which most were sent to China to be recycled. Poof! No more Developer Transition Kits.

Or are there? YouTuber dosdude1 found that these “recycled” kits could be purchased from China for basically the price of scrap. But interestingly, many of them are still largely intact, which means that they are almost fully functional computers. After purchasing one such kit, with an A12Z-based SoC, dosdude1 set out to repair it and get it up and running once again.

There were a few problems with the kit that were immediately obvious. The NAND chips, which are used for long-term storage, had been removed (as well as a few resistors and capacitors that serve as support chips). Furthermore, and much more concerningly, the PCB itself had been cut — most likely intentionally. In any case, the cut caused the inner layers of this densely-packed eight to 12 layer (the exact count is not known) PCB to short together.

While the cut was concerning, it did not prove to be fatal. There were no traces running through this area, so dosdude1 came up with an approach that involved widening the cut in the board, before sanding it with a variety of files. By continuously monitoring the electrical continuity between layers with a multimeter, it was possible to file the board down until the shorts were eliminated, and then stop before any further work was done — going too far could render the board virtually useless.

As for the missing NAND chips and supporting components, the fix was much easier. These components were simply scavenged from other donor boards and soldered in place. Before soldering it down, the NAND chip had to be formatted for use with the computer. Finally, MacOS was installed on the development kit by putting it into Device Firmware Update (DFU) mode and running the installer.

At this stage, it kind of worked. But since the original NAND chip, which stored the device’s serial number and MAC addresses, was gone the OS activation process failed. Fortunately, there are factory data recovery servers that one can access to recover this information, which is exactly what dosdude1 did. After updating the NAND chips accordingly, then reinstalling the OS, the developer kit finally came fully back to life.

To complete the build, dosdude1 fit the board into a Mac Mini case, connected the antennas, heat sink, front panel buttons, and so on. The final result was a pretty nice Mac Mini that was purchased for the price of scrap materials. Not a bad deal if you ask me. Even if you have no interest in trying to build your own four-year-old FrankenMac, the video is still well worth a watch for the troubleshooting tips offered up by dosdude1.