GPUFits
GPUs / Mac Studio M5 Ultra (96GB)
Mac Studio M5 Ultra (96GB) for Local LLMs: What It Runs and How Fast
The Mac Studio M5 Ultra 96GB is Apple's new flagship, announced August 25, 2026 and shipping September 22: 1.2TB/s of unified-memory bandwidth — the highest Apple has ever shipped, 50% above the M3 Ultra — at a $5,499 starting price, just $200 above the repriced M3 Ultra. Usable memory is the same ~72GB: gpt-oss-120b Q4 (~73.6GB) still misses by a hair, Q3_K_M (~60GB) is tight, 70B Q6_K (~62GB) is comfortable; but everything that fits runs about half again as fast — gpt-oss-120b theoretically ~288 tok/s, dense 70B ~21 tok/s.
The real choice is 96GB Ultra versus 128GB M5 Max (614GB/s): if your working set fits in 72GB, take the Ultra's bandwidth; only 85-100GB working sets justify the 128GB Max. The 256GB Ultra (+~$4,000) is the tier that genuinely changes the big-model map — Qwen3.8-Flash-Next Q4 (~112.6GB) and GLM-5.3-Flash 3-bit (~129GB) both fit comfortably; the 512GB version ships in late October. Up to four Mac Studios can pool memory over Thunderbolt 5. tdpW is a whole-system estimate.
Specs
| Nominal VRAM | 96 GB |
| Usable VRAM (for models) | 72.0 GB |
| Memory bandwidth | 1200 GB/s |
| Type | Unified memory |
| Release year | 2026 |
| MSRP | $5,499 |
| TDP | 140 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 | ≈140 tok/s | Try it → |
| Llama 3.1 8B | 7.5 GB | Comfortable | FP16 | ≈56 tok/s | Try it → |
| Qwen3 8B | 7.7 GB | Comfortable | FP16 | ≈55 tok/s | Try it → |
| Phi-4 14B | 12.2 GB | Comfortable | FP16 | ≈31 tok/s | Try it → |
| Mistral Small 3.2 24B | 17.5 GB | Comfortable | FP16 | ≈19 tok/s | Try it → |
| Gemma 3 27B | 22.4 GB | Comfortable | FP16 | ≈16 tok/s | Try it → |
| Qwen3.8 27B | 20.7 GB | Comfortable | FP16 | ≈16 tok/s | Try it → |
| Muse Glimmer 30B | 20.1 GB | Comfortable | FP16 | ≈15 tok/s | Try it → |
| Qwen3 30B-A3B | 21.0 GB | Comfortable | FP16 | ≈136 tok/s | Try it → |
| Qwen3 32B | 23.7 GB | Comfortable | FP16 | ≈14 tok/s | Try it → |
| gpt-oss-20b | 14.7 GB | Comfortable | FP16 | ≈125 tok/s | Try it → |
| Llama 3.3 70B | 47.4 GB | Comfortable | Q6_K | ≈16 tok/s | Try it → |
| gpt-oss-120b | 73.6 GB | Needs multi-GPU | Q3_K_M | ≈353 tok/s | Try it → |
| Qwen3.8 Flash-Next | 112.6 GB | Not feasible | needs 2 cards | — | Try it → |
| GLM-5.3-Flash | 198.7 GB | Not feasible | needs 3 cards | — | 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 M5 Ultra 96GB run?
- With ~72GB usable, capacity conclusions match the M3 Ultra: 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. The difference is speed: 1.2TB/s makes whatever fits run ~50% faster.
- 96GB M5 Ultra or 128GB M5 Max?
- If the target model fits within 72GB usable: take the Ultra — 1.2TB/s vs 614GB/s is nearly 2×. If the real working set is 85-100GB (e.g. an 80-90GB model file): the 128GB Max — bandwidth cannot accelerate weights that never fit. ~119GB-class Q4 models fit neither; that needs the 256GB Ultra.
- Is it worth $200 over the M3 Ultra?
- Yes. Local LLM generation is bandwidth-bound, so 1.2TB/s vs 819GB/s converts directly into ~+50% tok/s, and the M5 Ultra's per-GPU-core Neural Accelerators speed up long-prompt processing too. The only reason to pick an M3 Ultra is a clearly cheaper used/discounted channel.
Related guides
- Mac vs GPU for LLM Inference: Unified Memory Explained
- Why Memory Bandwidth Determines LLM Inference Speed
- MoE Model Hardware Requirements: Total vs Active Parameters
Try Mac Studio M5 Ultra (96GB) in the GPU compatibility checker →
Data verified 2026-10-01