Developer Transition Kit (2005)



The 2005 Developer Transition Kit (DTK), also known as the Developer Transition System (DTS), was an early Intel Mac made available for lease to developers enrolled in the Apple Developer Connection service. The DTK was sold to developers for US$999.

As with the Apple TV (1st generation), the DTK made use of a platform that was never used on a retail Mac. Specifically, it used the Intel Pentium 4 "Prescott" platform, based on the failed NetBurst microarchitecture, while the first retail Macs used the Core Duo "Merom" platform, based on the Core microarchitecture.

Hardware

 * CPU Specs:
 * Core Design: Intel "Prescott" Pentium 4 660 x 1
 * CPU Speed: 3.6 GHz
 * GPU Specs:
 * Core Design: Intel GMA 900
 * GPU Speed: 800 MHz
 * RAM: 1 GiB 533 MHz DDR2 ECC SDRAM
 * Storage: 160 GB
 * Firmware: Modified build of Mac OS X 10.4
 * Initial firmware: 10.4.1
 * Last firmware: 10.4.3
 * Internal Name:

PC Similarities
The hardware of the DTK is notable for being extremely similar to a traditional x86-based PC of the time. The logic board is not an Apple design - it is a modified Intel Desktop Board D915GUX, with a BIOS build customised to meet Apple's requirements, and rear I/O connectors matching those of the unmodified Power Mac G5 case. The machine additionally uses the legacy Master Boot Record scheme, rather than the GPT and Extensible Firmware Interface (EFI) scheme used by shipping Intel Macs, presumably as Apple's boot firmware implementation had not yet been finalised.

While the machine was configured to use the Intel 915 chipset's integrated Intel GMA 900 GPU, no video output was present on the logic board itself. A PCI Express card provided the video output functionality. This worked around the lack of onboard video output connector on the unchanged Power Mac G5 case. Unlike any retail Mac Pro, which exclusively uses PCI Express, the DTK logic board otherwise provided two legacy PCI slots.

Influence on Hackintoshing
The DTK, and subsequent online leaks of its restore DVDs featuring unique builds of Mac OS X Tiger, prompted the creation of the "Hackintosh" movement, which produces tools and patches enabling macOS to successfully boot on non-Apple hardware, and make use of hardware components not supported by the set of drivers built into the operating system.

The DTK featured an Infineon Trusted Platform Module (TPM), required for the machine to successfully boot into Mac OS X, in an attempt to prevent straightforward installation of the modified Mac OS X build onto similar non-Apple hardware. The security check is implemented in the Rosetta emulation layer, which allowed PowerPC apps to seamlessly run on an Intel Mac. Should the TPM challenges fail, Rosetta would refuse to start. A critical operating system component, ATSServer (Apple Type System daemon), was included as a PowerPC-only binary, thereby requiring the TPM check to pass for Mac OS X to boot into a graphical interface. Cracked releases of the Mac OS X builds patched out the TPM requirement, allowing it to be installed on similar non-Apple hardware with a "Prescott" Pentium 4 and Intel 915 chipset. Further patches developed by the community enabled it to run on a wider range of platforms, such as Intel Pentium M and AMD Athlon 64.

While some retail Macs shipped with TPM hardware, the operating system did not make use of it, and subsequent Macs removed the TPM. Retail Intel Macs instead used the System Management Controller and Dont Steal Mac OS.kext (DSMOS) to implement a hardware check that occurs much earlier in the boot process.