What LLMs can an M3 Ultra Mac Studio (512 GB) run?

An M3 Ultra Mac Studio (512 GB), with 384 GB usable by the GPU, runs 58 of the 69 open models tracked here at Q4_K_M with 8K context; the largest is Ling 3.1 Flash 560B-A25B (572.1B parameters, 355 GB). It reads memory at 819 GB/s; about 75% of unified memory is usable by the GPU. 7 more fit at a lower precision. Each fit leaves at least 0.5 GB free on the M3 Ultra Mac Studio (512 GB) (why a card does not give a model all its memory).

Models that fit on one M3 Ultra Mac Studio (512 GB)

The most precise weights that still fit with 8K tokens of context and one request, the memory that takes, the longest context at that precision and the writing speed. Bigger models come first. gpt-oss-120b (67.7 GB, 69–121 tokens/s on the M3 Ultra Mac Studio (512 GB)) and gpt-oss-20b (14.8 GB, 83–147 tokens/s on the M3 Ultra Mac Studio (512 GB)) are listed at MXFP4 only, as published.

Model Best precision Memory Longest context Tokens/s
Hy4 Preview 770B-A49B 780.0B, 49B active GGUF Q2_K 336 GB 498K 11–19
DeepSeek V4.1 Flash 1017 763.2B, 16B active GGUF Q3_K_M 383 GB 9K 28–47
DeepSeek V4.1 Flash 763.2B, 16B active GGUF Q3_K_M 383 GB 9K 28–47
GLM-5.3 753.3B, 40B active GGUF Q3_K_M 378 GB 59K 12–20
GLM-5.2 753.3B, 40B active GGUF Q3_K_M 378 GB 59K 12–20
DeepSeek V3.2 685.4B, 37B active GGUF Q3_K_M 344 GB 160K (full) 13–22
DeepSeek V3 / R1 684.5B, 37B active GGUF Q3_K_M 344 GB 160K (full) 13–22
Ling 3.1 Flash 560B-A25B 572.1B, 25B active GGUF Q4_K_M 355 GB 256K (full) 16–27
MiniMax M3 427.0B, 23B active GGUF Q6_K 360 GB 188K 12–20
GLM-5.3 Flash 321.3B, 18B active GGUF Q8_0 350 GB 1M (full) 13–21
IQuest-Q1 320B-A15B 320.3B, 15B active GGUF Q8_0 351 GB 308K 13–23
MiMo V2.6 Flash 310.8B, 15B active GGUF Q8_0 339 GB 1M (full) 15–25
DeepSeek V4 Flash 0731 304.2B, 13B active GGUF Q8_0 332 GB 561K 16–28
DeepSeek V4 Flash 290.9B, 13B active GGUF Q8_0 318 GB 717K 16–28
MiniMax M2.7 228.7B, 10B active GGUF Q8_0 252 GB 200K (full) 19–32
Step 3.7 Flash 196B-A11B 201.4B, 11B active GGUF Q8_0 220 GB 256K (full) 20–33
Qwen3.8 Flash Next 180.0B, 6B active FP16 / BF16 370 GB 256K (full) 20–33
Mistral Medium 3.5 128B 127.7B FP16 / BF16 265 GB 256K (full) 1.7–2.4
Qwen3.5 122B-A10B 125.1B, 10B active FP16 / BF16 257 GB 256K (full) 12–20
Nemotron 3.5 Super VL 120B-A12B 124.5B, 12B active FP16 / BF16 256 GB 1M (full) 10–17
Nemotron 3 Super 120B-A12B 123.6B, 12B active FP16 / BF16 254 GB 256K (full) 10–17
gpt-oss-120b 116.8B, 5.1B active As published (MXFP4) 67.7 GB 128K (full) 69–121
AliceAI Foundation 80B-A3B 81.3B, 3B active FP16 / BF16 167 GB 256K (full) 37–64
Qwen3-Coder-Next 79.7B, 3B active FP16 / BF16 164 GB 256K (full) 37–64
Kolibri-1 78.1B, 3.5B active FP16 / BF16 161 GB 256K (full) 33–55
Llama 3.1 70B 70.6B FP16 / BF16 148 GB 128K (full) 3.1–4.3
K2-Horizon MoVA 36B-A4B 37.4B, 4B active FP16 / BF16 78.9 GB 512K (full) 25–42
Ornith 1.5 35B-A3B 36.0B, 3B active FP16 / BF16 74.3 GB 256K (full) 38–64
Qwen3.6 35B-A3B 36.0B, 3B active FP16 / BF16 74.3 GB 256K (full) 38–64
Ornith 1.0 35B 35.1B, 3B active FP16 / BF16 72.6 GB 256K (full) 38–64
LLM-jp-4.1 32B-A3B Thinking 32.1B, 3.8B active FP16 / BF16 66.9 GB 64K (full) 29–49
Nemotron 3 Nano 30B-A3B 31.6B, 3.5B active FP16 / BF16 65.3 GB 256K (full) 33–56
Gemma 4 31B 31.3B FP16 / BF16 66.6 GB 256K (full) 6.9–9.5
GLM-4.7 Flash 31.2B, 3B active FP16 / BF16 64.9 GB 198K (full) 36–62
Xing 4.0 29B-A4B 31.2B, 4B active FP16 / BF16 64.8 GB 256K (full) 28–48
Qwen3-Coder 30B-A3B 30.5B, 3.3B active FP16 / BF16 63.9 GB 256K (full) 32–54
Qwen3 30B-A3B 30.5B, 3.3B active FP16 / BF16 63.9 GB 40K (full) 32–54
Muse Glimmer 30B 29.8B FP16 / BF16 61.7 GB 128K (full) 7.5–10
Granite 4.2 30B 29.3B FP16 / BF16 62.7 GB 128K (full) 7.3–10
ThinkingCap Qwen3.8 27B 27.8B FP16 / BF16 58.0 GB 256K (full) 7.9–11
Qwen3.6 27B 27.8B FP16 / BF16 58.0 GB 256K (full) 7.9–11
Qwen3.8 27B 27.8B FP16 / BF16 58.0 GB 256K (full) 7.9–11
Hemmingway-1 27B 27.3B FP16 / BF16 57.0 GB 256K (full) 8.1–11
Gemma 4 26B-A4B 25.8B, 4B active FP16 / BF16 53.9 GB 256K (full) 28–47
gpt-oss-20b 20.9B, 3.6B active As published (MXFP4) 14.8 GB 128K (full) 83–147
Gemma 4 12B 12.0B FP16 / BF16 25.7 GB 256K (full) 18–25
ZDTaichu 5.0 9B 9.8B FP16 / BF16 20.8 GB 128K (full) 22–30
Ornith 1.5 9B 9.7B FP16 / BF16 20.6 GB 256K (full) 22–31
Qwen3.5 9B 9.7B FP16 / BF16 20.6 GB 256K (full) 22–31
LensVLM 9B 9.4B FP16 / BF16 20.1 GB 256K (full) 23–32
Ornith 1.0 9B 9.4B FP16 / BF16 20.1 GB 256K (full) 23–32
MiMo V2.6 Distill Qwen 9B 9.4B FP16 / BF16 20.1 GB 256K (full) 23–32
Bespoke Nimble 9B 9.0B FP16 / BF16 19.1 GB 8K (full) 24–33
Granite 4.2 8B 8.8B FP16 / BF16 19.9 GB 128K (full) 23–32
LFM2.5 8B-A1B 8.5B, 1.5B active FP16 / BF16 18.0 GB 128,000 (full) 71–124
Qwen3 8B 8.2B FP16 / BF16 18.5 GB 40K (full) 25–34
Llama 3.1 8B 8.0B FP16 / BF16 18.1 GB 128K (full) 25–35
Gemma 4 E4B 8.0B FP16 / BF16 17.1 GB 128K (full) 27–37
Ling 3.0 Tiny 7.9B-A1.3B 7.9B, 1.3B active FP16 / BF16 16.7 GB 128K (full) 81–143
LightOnOCR-3 4B 4.5B FP16 / BF16 10.1 GB 256K (full) 45–64
Spark-X2.5 4B 4.1B FP16 / BF16 9.35 GB 1M (full) 48–69
Nemotron 3 Nano 4B 4.0B FP16 / BF16 8.78 GB 256K (full) 51–73
Granite 4.2 3B 3.7B FP16 / BF16 8.69 GB 128K (full) 52–74
MiniCPM5 2B 2.5B FP16 / BF16 6.02 GB 128K (full) 74–108
Limite 1B Violetto 1.0B FP16 / BF16 2.79 GB 128K (full) 155–241

Raising the GPU memory limit on an M3 Ultra Mac Studio (512 GB)

macOS lets the GPU wire about 384 GB of this Mac's 512 GB by default. Running sudo sysctl iogpu.wired_limit_mb=516096 raises that to 504 GB, leaving 8 GB to macOS and the apps next to it, until the next restart (macOS 14 or newer; iogpu.wired_limit_mb=0 restores the default). LM Studio and Ollama pick the new limit up after a restart of the app. At 504 GB, 65 of the 69 models fit at Q4_K_M with 8K context, against 58 by default : DeepSeek V3 / R1 (11–18 tokens/s), DeepSeek V3.2 (11–18 tokens/s), GLM-5.3 (9.7–16 tokens/s), GLM-5.2 (9.7–16 tokens/s), DeepSeek V4.1 Flash 1017 (23–39 tokens/s), DeepSeek V4.1 Flash (23–39 tokens/s) and Hy4 Preview 770B-A49B (8.0–13 tokens/s) join the list. If macOS runs short of memory it swaps or kills apps, so close big apps first and raise the limit in steps. How much unified memory a Mac's GPU can use, and why.

Too big for M3 Ultra Mac Studio (512 GB) at 8K context

How much memory each of these lacks at Q4_K_M with 8K context, one request and 0.5 GB kept free, out of the 384 GB usable here; a bigger machine or a smaller quant is the way in.

Best models for M3 Ultra Mac Studio (512 GB) with room for long context

The biggest models that still fit at Q4_K_M with 32,768 tokens of context (or their whole window, if shorter), the memory left over, the longest context the Mac takes at that precision and the writing speed with that context in the cache, from 819 GB/s of bandwidth.

ModelContextMemoryLeft overLongest contextTokens/s
Ling 3.1 Flash 560B-A25B 572.1B 32K 355 GB 28.6 GB 256K (full) 16–26
MiniMax M3 427.0B 32K 269 GB 115 GB 917K 13–23
GLM-5.3 Flash 321.3B 32K 200 GB 184 GB 1M (full) 21–35
IQuest-Q1 320B-A15B 320.3B 32K 204 GB 180 GB 512K (full) 18–30
MiMo V2.6 Flash 310.8B 32K 194 GB 190 GB 1M (full) 24–40

llama-server commands for an M3 Ultra Mac Studio (512 GB)

GGUF repos checked 2026-09-29; -c is the longest context with 0.5 GB free on the M3 Ultra Mac Studio (512 GB). No -ngl: llama.cpp’s -fit, on by default since b7440, places the layers.

MiniMax M3, Q4_K_M with 872K tokens: 2.0–3.3 tokens/s on the M3 Ultra Mac Studio (512 GB)

llama-server -hf unsloth/MiniMax-M3-GGUF:Q4_K_M -c 892928

UD-Q4_K_M/MiniMax-M3-UD-Q4_K_M-00001-of-00007.gguf, 264.0 GB: 383 GB used and 620 MB free of the M3 Ultra Mac Studio (512 GB)'s 384 GB usable, 2.0–3.3 tokens/s once the 872K cache is full.

How fast the M3 Ultra Mac Studio (512 GB) writes as the context fills

Tokens per second at Q4_K_M for the biggest models that fit with 32K tokens, with 8K and 32K tokens in the cache and at the longest context the Mac holds, and at Q8_0 with 8K where that fits. Each token reads the active weights and the whole cache once, so the speed follows the 819 GB/s of bandwidth and falls as the cache grows. The ceiling is that bandwidth divided by the bytes read per token, which no runtime reaches; the reply time is for 1,000 new tokens with 32K (or the longest context) in the cache, prompt processing aside.

Model8K32KLongestAt the longestQ8_0 at 8KBandwidth ceiling at 8K1,000-token reply at 32K
Ling 3.1 Flash 560B-A25B 16–27 16–26 256K 13–23 Does not fit 54 38–64 s
MiniMax M3 16–27 13–23 917K 1.9–3.2 Does not fit 55 44–75 s
GLM-5.3 Flash 22–36 21–35 1M 7.7–13 13–21 74 29–48 s
IQuest-Q1 320B-A15B 21–36 18–30 512K 3.8–6.4 13–23 74 34–57 s
MiMo V2.6 Flash 25–43 24–40 1M 7.3–12 15–25 87 25–42 s
DeepSeek V4 Flash 0731 27–47 22–37 1M 2.4–4.1 16–28 95 27–45 s
DeepSeek V4 Flash 27–47 22–37 1M 2.4–4.1 16–28 95 27–45 s
MiniMax M2.7 29–49 17–28 200K 4.2–7.0 19–32 101 36–60 s
Step 3.7 Flash 196B-A11B 32–55 28–48 256K 12–21 20–33 114 21–36 s
Qwen3.8 Flash Next 59–101 51–88 256K 24–40 35–60 214 11–20 s

Near misses on M3 Ultra Mac Studio (512 GB)

Models that miss at Q4_K_M with 32,768 tokens of context (or their whole window), or leave under 0.5 GB free there, but fit with a shorter context or 3-bit weights, or are short by at most a quarter of the memory and fit with MoE offload. Smallest shortfall first.

ModelShort by at Q4_K_MFits instead
DeepSeek V3 / R1 684.5B 43.1 GB GGUF Q3_K_M with 32K, 346 GB
DeepSeek V3.2 685.4B 43.9 GB GGUF Q3_K_M with 32K, 346 GB
GLM-5.3 753.3B 86.5 GB GGUF Q3_K_M with 32K, 381 GB
GLM-5.2 753.3B 86.5 GB GGUF Q3_K_M with 32K, 381 GB
DeepSeek V4.1 Flash 1017 763.2B 92.3 GB GGUF IQ3_XXS with 32K, 326 GB

Run locally or rent an M3 Ultra Mac Studio (512 GB)?

getdeploying.com lists no on-demand rental of M3 Ultra Mac Studio (512 GB) (checked ). None of the GPUs this site tracks has 384 GB of memory on one card; rent several cards or compare multi-GPU servers on the same index.

How these numbers are worked out

Memory is the weights at each precision plus the KV cache for 8,192 tokens in FP16 and runtime overhead (0.5 GB plus 10%), computed from each model's files on Hugging Face with the LLM VRAM Calculator. Speed is estimated from memory bandwidth and the parameters read per token with the LLM Speed Calculator. Both tools take any other model from Hugging Face.

Nearby GPUs and setups

How many of the tracked models each one holds at Q4_K_M with 8K context, against 58 here.

SetupHow it relatesMemoryBandwidthModels at Q4_K_M
B200 Next size down 180 GB 8,000 GB/s 51 (−7)
8× H100 SXM Next size up 640 GB 26,800 GB/s 66 (+8)

Model numbers read from Hugging Face on .