Apple announced the M3 on October 30, 2023, at its Halloween-themed Scary Fast online event,[4] along with models of the iMac and the MacBook Pro using the M3.[5][6][7]
Design
The M3 series is Apple's first 3 nm design for desktops and notebooks. It is manufactured by TSMC.[8][9]
CPU
M3: 8-core CPU with 4 performance cores and 4 efficiency cores
M3 Pro: 11- or 12-core CPU with 5 or 6 performance cores and 6 efficiency cores
M3 Max: 14- or 16-core CPU with 10 or 12 performance cores and 4 efficiency cores
GPU
The redesigned GPU includes features like Dynamic Caching, Mesh Shading, and hardware-accelerated ray tracing.[10]
The Dynamic Caching technology allocates local memory in real time. Unlike conventional approaches, Dynamic Caching ensures that only the precise amount of memory required for a task is used, thereby optimizing memory usage and potentially enhancing performance and efficiency. This is particularly beneficial for graphics-intensive tasks, where dynamic memory allocation can be critical.[11]
The M3 contains dedicated neural network hardware in a 16-core Neural Engine capable of executing over 18 trillion operations per second, which is slower than the A17 Pro's 35 trillion operations per second NPU seen in the iPhone 15 Pro series.
AI
Apple specifically targeted AI development and workloads, both with the Neural Engine and with the increased maximum memory (128 GiB) of the M3 Max, allowing AI models with high numbers of parameters. Apple claims a 15% performance improvement for AI workloads on the M3 (compared to the previous generation M2). [13]
Memory
The M3's Unified Memory Architecture (UMA) is similar to the M2 generation; M3 SoCs use 6,400 MT/sLPDDR5 SDRAM. As with prior M series SoCs, this serves as both RAM and video RAM. The M3 has 8 memory controllers, the M3 Pro has 12 and the M3 Max has 32. Each controller is 16-bits wide and is capable of accessing up to 4 GiB of memory.[14]
The M3 Pro and 14-core M3 Max have lower memory bandwidth than the M1/M2 Pro and M1/M2 Max respectively. The M3 Pro has a 192-bit memory bus where the M1 and M2 Pro had a 256-bit bus, resulting in only 150 GB/sec bandwidth versus 200 GB/sec for its predecessors. The 14-core M3 Max only enables 24 out of the 32 controllers, therefore it has 300 GB/sec vs. the 400 GB/sec for all models of the M1 and M2 Max, while the 16-core M3 Max has the same 400 GB/sec as the prior M1 and M2 Max models.[15]