Apple develops its own Arm-based CPUs and GPUs in SoCs and SIPs for the iOS, iPadOS, tvOS and watchOS devices.
Apple has reached the technological milestones required to build their own SoCs, SIPs and other microprocessors for the Mac devices closely based on Apple's existing Arm-based CPUs and GPUs along with their class-leading neural networks accelerators.
Intel will be steadily replaced in Apple devices over the two-year window.
The first devices will be similar to the top-of-the-range iPad Pro; however, it will feature eight Arm cores.
AMD has a graphics partnership with Apple; it will be interesting to see whether this is maintained following the migration to Apple's processors.
NVIDIA has not been officially supported since 2012. NVIDIA is focussing on other platforms despite continually scouting for Mac driver specialists.
We are yet to hear what the Mac Pro platform will become with Apple processors; will it feature user-upgradable GPUs in the MPX platform?