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Apple M3 Ultra (512GB) vs Apple M2 Ultra (192GB)

Side-by-side local AI comparison — VRAM, memory bandwidth, model compatibility, and estimated tokens per second across 84 open-weight models.

Quick verdict

Apple M3 Ultra (512GB) wins for local AI inference. It has 320 GB more VRAM and 2% more memory bandwidth, runs 82 models natively (vs 71), and exclusively fits 11 models the other cannot.

Specs comparison

SpecApple M3 Ultra (512GB)Apple M2 Ultra (192GB)
VRAM512 GB unified192 GB unified
Memory typeLPDDR5XLPDDR5
Bandwidth819 GB/s(+2%)800 GB/s
CPU cores32 (24P + 8E)24 (16P + 8E)
ArchitectureApple M3 UltraApple M2 Ultra
BackendMETALMETAL
TierWorkstationWorkstation
Released20252023
Models (native)8271

Estimated tokens per second

Computed from memory bandwidth and model active-parameter weight. Assumes model fits natively in VRAM.

ModelApple M3 Ultra (512GB)Apple M2 Ultra (192GB)Delta
Llama 3.3 70B Instruct(70B)2.3 t/s(FP32)4.5 t/s(BF16)-49%
Qwen 3.6 27B(27B)6 t/s(FP32)5.9 t/s(FP32)+2%
Llama 3.1 8B Instruct(8B)19.8 t/s(FP32)19.4 t/s(FP32)+2%
Qwen 2.5 7B Instruct(7.6B)21.2 t/s(FP32)20.7 t/s(FP32)+2%

Delta is Apple M3 Ultra (512GB) relative to Apple M2 Ultra (192GB).

Only Apple M3 Ultra (512GB) can run(11)

Only Apple M2 Ultra (192GB) can run(0)

No exclusive models — Apple M3 Ultra (512GB) can run everything Apple M2 Ultra (192GB) can.

Both run natively(71)

These models fit in VRAM on both GPUs. Bandwidth determines which runs them faster.

Which should you choose?

Choose Apple M3 Ultra (512GB) if:
  • • You need to run larger models (>192 GB VRAM)
  • • Faster token generation is the priority
  • • You want the newer architecture and longer driver support lifecycle
Choose Apple M2 Ultra (192GB) if:

    Frequently asked questions

    Which is better for local AI, the Apple M3 Ultra (512GB) or Apple M2 Ultra (192GB)?
    For local AI inference, the Apple M3 Ultra (512GB) has the edge. It offers 512 GB VRAM (vs 192 GB) and 819 GB/s bandwidth (vs 800 GB/s), letting it run 82 models natively in VRAM vs 71 for its rival.
    How much VRAM does the Apple M3 Ultra (512GB) have vs the Apple M2 Ultra (192GB)?
    The Apple M3 Ultra (512GB) has 512 GB of LPDDR5X at 819 GB/s. The Apple M2 Ultra (192GB) has 192 GB of LPDDR5 at 800 GB/s. The Apple M3 Ultra (512GB) has 320 GB more VRAM, allowing it to run 11 models the Apple M2 Ultra (192GB) cannot fit natively.
    Can the Apple M3 Ultra (512GB) run Llama 3.3 70B?
    Yes. The Apple M3 Ultra (512GB) runs Llama 3.3 70B natively at FP32 quantization at approximately 2.3 tokens per second.
    Can the Apple M2 Ultra (192GB) run Llama 3.3 70B?
    Yes. The Apple M2 Ultra (192GB) runs Llama 3.3 70B natively at BF16 quantization at approximately 4.5 tokens per second.
    What is the difference between the Apple M3 Ultra (512GB) and Apple M2 Ultra (192GB) for AI?
    The key difference for AI inference is VRAM and memory bandwidth. The Apple M3 Ultra (512GB) has 512 GB VRAM at 819 GB/s (METAL backend). The Apple M2 Ultra (192GB) has 192 GB VRAM at 800 GB/s (METAL backend). VRAM determines which models fit; bandwidth determines tokens per second. The Apple M3 Ultra (512GB) runs 82 models natively vs 71 for the Apple M2 Ultra (192GB).
    Full Apple M3 Ultra (512GB) page →Full Apple M2 Ultra (192GB) page →Check your hardware →