Mac Studio Ultra with 512GB RAM enables local inference for world's largest LLMs

The 512GB Mac Studio is the ultimate capacity play for local LLM practitioners where memory volume outweighs raw inference speed.

• –512GB unified memory is the only viable path to run DeepSeek-R1 (671B) or Llama 3.1 405B at 4-bit quantization on a single consumer-grade device.
• –800GB/s memory bandwidth remains the primary bottleneck, yielding ~16-20 t/s for large models—functional but slow compared to multi-H100/A100 clusters.
• –The MLX framework is essential for performance, often providing a 2x speedup over standard llama.cpp implementations on Apple Silicon.
• –For users not targeting 400B+ models, the 128GB or 192GB configurations offer a significantly better price-to-performance ratio for fluid 70B model inference.