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Mac Studio M3 Ultra (96GB) for Local LLMs: What It Runs and How Fast
The Mac Studio M3 Ultra 96GB is the “near-datacenter” of local LLMs: 96GB unified memory with ~72GB usable and 819 GB/s bandwidth — gpt-oss-120b Q4 (~73.6GB) falls just short, Q3_K_M (~60GB) is tight, and 70B at Q6_K (~62GB) is comfortable. The pricing context matters: launched at $3,999, repriced to $5,299 on 2026-06-25, and since March 2026 Apple has discontinued the 256/512GB versions amid the DRAM shortage — 96GB is now the ceiling of what you can buy, which kills any single-Mac path to full DeepSeek-R1 (413GB+).
At 819 GB/s it runs MoE models extremely fast (gpt-oss-120b theoretically ~200 tok/s) and dense 70B at ~14 tok/s — ample capacity, middling bandwidth is the accurate profile. Buyers: developers and small teams needing 60-72GB of usable VRAM who refuse multi-GPU operations. At $5,299 it must be seriously cross-shopped against dual-4090/A6000 builds; if your target is just 70B Q4, the M4 Max 64GB saves $2,400.
Specs
| Nominal VRAM | 96 GB |
| Usable VRAM (for models) | 72.0 GB |
| Memory bandwidth | 819 GB/s |
| Type | Unified memory |
| Release year | 2025 |
| MSRP | $5,299 |
| TDP | 100 W |
Apple unified memory is counted at 75% usable for models (the rest serves the system/display).
Value Metrics
Based on MSRP (no used price yet); used prices are market estimates, see commentary for volatility.
Model Verdict Matrix (Q4_K_M @8K)
| Model | VRAM needed | Verdict | Recommended quant | Theoretical speed | |
|---|---|---|---|---|---|
| Llama 3.2 3B | 4.4 GB | Comfortable | FP16 | ≈96 tok/s | Try it → |
| Llama 3.1 8B | 7.5 GB | Comfortable | FP16 | ≈38 tok/s | Try it → |
| Qwen3 8B | 7.7 GB | Comfortable | FP16 | ≈37 tok/s | Try it → |
| Phi-4 14B | 12.2 GB | Comfortable | FP16 | ≈21 tok/s | Try it → |
| Mistral Small 3.2 24B | 17.5 GB | Comfortable | FP16 | ≈13 tok/s | Try it → |
| Gemma 3 27B | 22.4 GB | Comfortable | FP16 | ≈11 tok/s | Try it → |
| Qwen3.8 27B | 20.7 GB | Comfortable | FP16 | ≈11 tok/s | Try it → |
| Muse Glimmer 30B | 20.1 GB | Comfortable | FP16 | ≈10 tok/s | Try it → |
| Qwen3 30B-A3B | 21.0 GB | Comfortable | FP16 | ≈93 tok/s | Try it → |
| Qwen3 32B | 23.7 GB | Comfortable | FP16 | ≈9 tok/s | Try it → |
| gpt-oss-20b | 14.7 GB | Comfortable | FP16 | ≈85 tok/s | Try it → |
| Llama 3.3 70B | 47.4 GB | Comfortable | Q6_K | ≈11 tok/s | Try it → |
| gpt-oss-120b | 73.6 GB | Needs multi-GPU | Q3_K_M | ≈241 tok/s | Try it → |
| DeepSeek-R1 671B | 413.1 GB | Not feasible | — | — | Try it → |
Theoretical speed = bandwidth × 0.75 ÷ per-token weight bytes (active params for MoE); real-world results vary with framework/driver/CPU, ±30%.
FAQ
- What can the Mac Studio M3 Ultra 96GB run?
- With ~72GB usable: gpt-oss-120b Q3_K_M (~60GB) tight, 70B Q6_K (~62GB) comfortable, everything else comfortable. At Q4, gpt-oss-120b (73.6GB) misses by 1.6GB — drop a quant or go dual-machine.
- Why did the M3 Ultra price go up?
- The 2026 DRAM shortage: Apple discontinued the 256/512GB versions in March 2026 and repriced the 96GB model from $3,999 to $5,299 on 2026-06-25. 96GB is now Apple's single-machine memory ceiling.
- M3 Ultra 96GB or dual 4090s (48GB)?
- For 60GB+ capacity to hold 120B-class MoE: only the M3 Ultra (dual 4090s cap at 48GB). For ≤70B with the CUDA ecosystem: dual 4090s are faster and cheaper. The capacity cliff decides.
Related guides
- Mac vs GPU for LLM Inference: Unified Memory Explained
- MoE Model Hardware Requirements: Total vs Active Parameters
- Running DeepSeek-R1 Locally: The Complete Hardware Guide
Try Mac Studio M3 Ultra (96GB) in the GPU compatibility checker →
Data verified 2026-09-01