512GB VRAM

Mac M5 Ultra 512G — what LLMs can it run?

107 of 112 indexed models fit comfortably in 512GB at 4K context, each at the highest-quality quant that still leaves headroom.

The short answer for Mac M5 Ultra 512G

512 GB, 1,200 GB/s Unified LPDDR5X. 107 of 112 models in this index fit comfortably at 4K context; 111 load at all.

Biggest that fits
Muse Spark Open 816B-A42B — 318.9 GB at Q2_K — 65.1 GB spare at 4K, so longer context comes out of a thin margin.
Room to grow
Beam 1.0 501B-A23B — 190.9 GB at Q2_K — under 60% of the card, which leaves 193.1 GB for a long context window or a second process.
Speed ceiling
Llama 3.1 8B Instruct at Q4_K_M reads 4.6 GB of weights per token, so 1,200 GB/s puts a hard ceiling near 260 tok/s. That is arithmetic on two published numbers, not a benchmark — real throughput lands below it. No run on this card has been measured here, so there is nothing to compare the ceiling against.
The wall you will hit
The GPU's share of unified memory, not the 512 GB on the box. macOS reserves part of the pool for the system and caps what a single process may wire down, so the practical budget is meaningfully below nameplate — the limit is adjustable (`iogpu.wired_limit_mb`) but it is not absent. Bandwidth is 1,200 GB/s, which is the number that decides tok/s once a model fits.
Best local LLM for Apple silicon

70B+ · 18

Mac M5 Ultra 512G — what LLMs can it run? — 70B+
ModelQuantEst. VRAMHeadroomtok/s
Muse Spark Open 816B-A42B816B-A42BQ2_K318.88 GB+65.1 GB≤81Ceiling
Beam 1.0 501B-A23B501B-A23BQ2_K190.87 GB+193.1 GB≤151Ceiling
Llama 3.1 405B Instruct405BQ4_K_M258.73 GB+125.3 GB≤5Ceiling
Llama 4 Maverick 17B (128E)400B MoEQ4_K_M254.22 GB+129.8 GB≤123Ceiling
Qwen3 235B-A22B Instruct235B-A22BQ4_K_M149.68 GB+234.3 GB≤95Ceiling
DBRX Instruct132B MoEQ4_K_M84.31 GB+299.7 GB≤58Ceiling
Qwen3.8-Flash-Next125B-A6BQ8_0138.91 GB+245.1 GB≤198Ceiling
Nemotron 3.5 Super VL 120B-A12B120B-A12BQ8_0134.27 GB+249.7 GB≤99Ceiling
GPT-OSS 120B117B MoEMXFP466.4 GB+317.6 GB≤457Ceiling
Llama 4 Scout 17B (16E)109B MoEQ4_K_M69.88 GB+314.1 GB≤123Ceiling
GLM-4.5-Air106B MoEQ4_K_M67.94 GB+316.1 GB≤174Ceiling
Llama 3.2 90B Vision Instruct90BQ4_K_M57.5 GB+326.5 GB≤24Ceiling
Nemotron 3.5 Bolt 74B-A9B74B-A9BIQ2_XXS23.05 GB+361 GB≤472Ceiling
Qwen2.5 72B Instruct72BQ5_K_M55.31 GB+328.7 GB≤24Ceiling
Llama 3.1 70B Instruct70BQ5_K_M53.75 GB+330.3 GB≤25Ceiling
Llama 3.3 70B Instruct70BQ5_K_M53.75 GB+330.3 GB≤25Ceiling
DeepSeek-R1-Distill-Llama-70B70BQ4_K_M46.1 GB+337.9 GB≤30Ceiling
Jamba 1.5 Mini52B-A12BQ4_K_M33.01 GB+351 GB≤174Ceiling

32B · 31

Mac M5 Ultra 512G — what LLMs can it run? — 32B
ModelQuantEst. VRAMHeadroomtok/s
Kimi Linear 48B-A3B Instruct48B-A3BQ8_053.33 GB+330.7 GB≤396Ceiling
Mixtral 8x7B Instruct47B MoEQ4_K_M30.13 GB+353.9 GB≤162Ceiling
Seed-OSS 36B Instruct36BQ5_K_M27.81 GB+356.2 GB≤49Ceiling
Qwen3.6 35B-A3B35B-A3BQ8_039.6 GB+344.4 GB≤396Ceiling
Command R 35B35BQ4_K_M22.86 GB+361.1 GB≤60Ceiling
Yi 1.5 34B Chat34BQ4_K_M22.82 GB+361.2 GB≤61Ceiling
Qwen3 32B Instruct32BQ4_K_M21.85 GB+362.2 GB≤64Ceiling
Qwen2.5 32B Instruct32BQ4_K_M21.69 GB+362.3 GB≤64Ceiling
Qwen2.5-Coder 32B Instruct32BQ4_K_M21.69 GB+362.3 GB≤64Ceiling
DeepSeek-R1-Distill-Qwen-32B32BQ4_K_M21.69 GB+362.3 GB≤64Ceiling
Nemotron 3.5 Lightning 30B-A3B30B-A3BQ8_035.14 GB+348.9 GB≤396Ceiling
Gemma 4 31B IT31BQ8_035.72 GB+348.3 GB≤39Ceiling
Qwen3 30B-A3B Instruct30B-A3BQ5_K_M23.04 GB+361 GB≤593Ceiling
Qwen3-Coder 30B-A3B Instruct30B-A3BQ5_K_M23.04 GB+361 GB≤593Ceiling
Qwen3-VL 30B-A3B Instruct30B-A3BQ8_034.28 GB+349.7 GB≤396Ceiling
North Mini Code 1.0 30B-A3B30B-A3BQ8_034.3 GB+349.7 GB≤396Ceiling
GLM-4.7-Flash30B-A3BQ8_033.47 GB+350.5 GB≤396Ceiling
Granite 4.2 30B30BQ8_033.61 GB+350.4 GB≤41Ceiling
Muse Glimmer 30B30BQ8_031.08 GB+352.9 GB≤43Ceiling
Qwen3.8 27B27BQ4_K_M17.47 GB+366.5 GB≤77Ceiling
Qwen3.6 27B27BQ8_030.71 GB+353.3 GB≤43Ceiling
Gemma 3 27B IT27BQ4_K_M18.37 GB+365.6 GB≤76Ceiling
Gemma 2 27B Instruct27BQ5_K_M21.76 GB+362.2 GB≤65Ceiling
Gemma 4 26B-A4B IT26B-A4BQ8_028.42 GB+355.6 GB≤297Ceiling
Mistral Small 24B Instruct24BQ4_K_M15.89 GB+368.1 GB≤87Ceiling
LFM2.5 24B-A2B24B-A2BQ8_026.73 GB+357.3 GB≤485Ceiling
Devstral Small 1.1 24B24BQ6_K20.91 GB+363.1 GB≤65Ceiling
Magistral Small 1.2 24B24BQ6_K20.91 GB+363.1 GB≤65Ceiling
Codestral 22B22BQ4_K_M15.03 GB+369 GB≤94Ceiling
ERNIE 4.5 21B-A3B21B-A3BQ8_024.44 GB+359.6 GB≤396Ceiling
GPT-OSS 20B21B MoEMXFP412.76 GB+371.2 GB≤606Ceiling

14B · 19

Mac M5 Ultra 512G — what LLMs can it run? — 14B
ModelQuantEst. VRAMHeadroomtok/s
InternLM2 20B Chat20BQ5_K_M15.59 GB+368.4 GB≤89Ceiling
DeepSeek-Coder-V2-Lite Instruct16B-A2.4BQ8_017.56 GB+366.4 GB≤495Ceiling
DeepSeek-V2-Lite Chat16B-A2.4BQ4_K_M10.08 GB+373.9 GB≤868Ceiling
StarCoder2 15B15BQ4_K_M10.19 GB+373.8 GB≤139Ceiling
Qwen3 14B Instruct14BQ5_K_M11.65 GB+372.4 GB≤120Ceiling
Qwen2.5 14B Instruct14BQ5_K_M11.73 GB+372.3 GB≤121Ceiling
DeepSeek-R1-Distill-Qwen-14B14BQ4_K_M10.14 GB+373.9 GB≤142Ceiling
Phi-4 14B14BQ5_K_M11.77 GB+372.2 GB≤121Ceiling
Phi-3 Medium 14B Instruct14BQ6_K12.86 GB+371.1 GB≤110Ceiling
Mistral Nemo 12B Instruct12BQ6_K11.14 GB+372.9 GB≤126Ceiling
Gemma 3 12B IT12BQ5_K_M9.84 GB+374.2 GB≤146Ceiling
Mellum2.1 12B-A2.5B Thinking12B-A2.5BQ8_013.6 GB+370.4 GB≤476Ceiling
Stable LM 2 12B Chat12BQ4_K_M8.35 GB+375.7 GB≤172Ceiling
Gemma 4 12B IT12BQ8_013.82 GB+370.2 GB≤100Ceiling
Llama 3.2 11B Vision Instruct11BQ8_012.9 GB+371.1 GB≤108Ceiling
Solar 10.7B Instruct11BQ4_K_M7.6 GB+376.4 GB≤195Ceiling
Falcon 3 10B Instruct10BQ4_K_M7.28 GB+376.7 GB≤200Ceiling
Gemma 2 9B Instruct9BQ8_011.7 GB+372.3 GB≤129Ceiling
Qwen3.5 9B9BQ8_010.37 GB+373.6 GB≤129Ceiling

7B · 25

Mac M5 Ultra 512G — what LLMs can it run? — 7B
ModelQuantEst. VRAMHeadroomtok/s
GLM-4-9B-Chat9BQ8_010.16 GB+373.8 GB≤132Ceiling
Qwen3-VL 8B Instruct8BQ8_010.39 GB+373.6 GB≤135Ceiling
Granite 4.2 8B8BQ8_010.45 GB+373.6 GB≤135Ceiling
Ministral 3 8B Instruct8BQ8_010.02 GB+374 GB≤140Ceiling
Qwen2-VL 7B Instruct7BQ4_K_M5.49 GB+378.5 GB≤252Ceiling
Granite 3.1 8B Instruct8BQ4_K_M5.88 GB+378.1 GB≤254Ceiling
Qwen3 8B Instruct8BQ6_K7.64 GB+376.4 GB≤188Ceiling
Llama 3.1 8B Instruct8BQ8_09.47 GB+374.5 GB≤148Ceiling
Nous Hermes 3 Llama 3.1 8B8BQ4_K_M5.64 GB+378.4 GB≤260Ceiling
Aya 23 8B8BQ4_K_M5.64 GB+378.4 GB≤260Ceiling
OpenChat 3.6 8B8BQ4_K_M5.64 GB+378.4 GB≤260Ceiling
DeepSeek-R1-Distill-Llama-8B8BQ5_K_M6.51 GB+377.5 GB≤221Ceiling
InternLM2 7B Chat7BQ4_K_M5.45 GB+378.6 GB≤269Ceiling
Qwen2.5 7B Instruct7BQ6_K6.77 GB+377.2 GB≤202Ceiling
Qwen2.5-Coder 7B Instruct7BQ4_K_M5.07 GB+378.9 GB≤273Ceiling
DeepSeek-R1-Distill-Qwen-7B7BQ4_K_M5.07 GB+378.9 GB≤273Ceiling
Gemma 4 E4B ITE4BQ8_08.46 GB+375.5 GB≤158Ceiling
OLMo 2 7B Instruct7BQ8_010.3 GB+373.7 GB≤163Ceiling
OLMo 3 7B Instruct7BQ8_010.3 GB+373.7 GB≤163Ceiling
WizardLM-2 7B7BQ4_K_M5.14 GB+378.9 GB≤288Ceiling
Mistral 7B Instruct v0.37BQ6_K6.75 GB+377.3 GB≤213Ceiling
Zephyr 7B Beta7BQ6_K6.75 GB+377.3 GB≤213Ceiling
Gemma 4 E2B ITE2BQ8_05.2 GB+378.8 GB≤256Ceiling
Qwen3.5 4B4BQ8_04.97 GB+379 GB≤273Ceiling
Gemma 3 4B IT4BQ8_05.05 GB+379 GB≤276Ceiling

≤3B · 14

Mac M5 Ultra 512G — what LLMs can it run? — ≤3B
ModelQuantEst. VRAMHeadroomtok/s
Qwen3 4B Instruct4BQ6_K4.05 GB+380 GB≤385Ceiling
Phi-4 Mini Instruct3.8BQ8_04.81 GB+379.2 GB≤309Ceiling
Phi-3.5 Mini Instruct3.8BQ8_05.89 GB+378.1 GB≤311Ceiling
Granite 4.2 3B3BQ8_04.41 GB+379.6 GB≤325Ceiling
Llama 3.2 3B Instruct3BQ8_04.05 GB+380 GB≤370Ceiling
Qwen2.5 3B Instruct3BQ8_03.59 GB+380.4 GB≤385Ceiling
SmolLM3 3B3BQ8_03.73 GB+380.3 GB≤386Ceiling
Gemma 2 2B Instruct2BQ8_03.34 GB+380.7 GB≤456Ceiling
Qwen3.5 2B2BQ8_02.23 GB+381.8 GB≤606Ceiling
Qwen3 1.7B Instruct1.7BQ8_02.39 GB+381.6 GB≤690Ceiling
Qwen2.5 1.5B Instruct1.5BQ8_01.83 GB+382.2 GB≤774Ceiling
Llama 3.2 1B Instruct1BQ8_01.51 GB+382.5 GB≤960Ceiling
Qwen3.5 0.8B0.8BQ8_00.94 GB+383.1 GB≤1481Ceiling
Qwen2.5 0.5B Instruct0.5BQ8_00.6 GB+383.4 GB≤2449Ceiling

How this list is built

Each row is the lowest-perplexity-loss quant of that model whose estimated total — weights plus KV cache at 4K context plus activation buffer — uses at most 88% of the card. That is the calculator's "green" threshold, so every row here has real headroom rather than only just fitting. Raise the context length and the list shortens; the calculator lets you check any combination directly. The speed column is this card: a measured run, a range scaled from this card's own Llama 2 7B benchmark, or a bandwidth ceiling. A figure that only exists for the RTX 4090 is labelled as that card.

A further 4 models load but with no headroom to spare (up to 105% of VRAM) — the Quant Hub’s GPU chips count those too, which is why its number is higher.

Measured on this card

No benchmark runs in this index were recorded on a Mac M5 Ultra 512G. Every figure on this page is calculated from the model architecture and the quant level — treat them as estimates, not measurements.

Setup guides for this card

Step-by-step guides written for the Mac M5 Ultra 512G's runtime or memory size, with the commands and the checks that prove the model is running on the card.

Common questions

What is the best local LLM for a Mac M5 Ultra 512G?

For everyday use, Beam 1.0 501B-A23B at Q2_K — about 190.9 GB of the card's 512 GB at 4K context, leaving 193.1 GB for a longer window. If you want the largest thing that will load, that is Muse Spark Open 816B-A42B at Q2_K (318.9 GB, 65.1 GB spare). "Best" here means best fit for the memory budget — this index does not run task benchmarks, so it cannot tell you which model is smarter.

Can a Mac M5 Ultra 512G run MiMo-V2.6-Pro?

No. Its smallest build here, MXFP4, needs about 603.8 GB and this card has 384.0 GB usable — short by 219.8 GB before any context beyond 4K. The largest model this card does clear is Muse Spark Open 816B-A42B.

How many tokens per second does a Mac M5 Ultra 512G do on an 8B model at Q4?

This index has no measured run on this card, so it does not publish a figure. What can be stated from specifications: generating a token requires reading every weight once, Llama 3.1 8B Instruct at Q4_K_M is 4.6 GB of weights, and this card moves 1,200 GB/s — a ceiling near 260 tok/s. Batch size, context length, the runtime and how much of the model sits in cache all take you below it.

Mac M5 Ultra 512G or Mac M5 Ultra 256G for local LLMs?

They do not hold the same set: Mac M5 Ultra 512G fits 107 and Mac M5 Ultra 256G 103 of 112 at 4K — macOS keeps part of the Mac M5 Ultra 512G's unified memory from the GPU, leaving about 384 GB usable. Speed is the other difference — 1,200 GB/s against 1,200 GB/s, a 1.0× gap in how fast the weights can be read, which is what token generation is bound by. The Mac M5 Ultra 512G generates faster on any model both can hold.

107 of 112 indexed models fit comfortably in 512GB at 4K context, each at the highest-quality quant that still leaves headroom.

This page's figures change when the model or the runtime does.Last updated 2026-10-20 RSS → /feed.xml