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URL: https://willitrunai.com/can-run/qwen-3.5-122b-a10b-on-m3-ultra-256gb

⇱ Qwen 3.5 122B A10B on Mac Studio M3 Ultra 256GB? YES


Can Qwen 3.5 122B A10B run on Mac Studio M3 Ultra 256GB?

YES — Runs Great

S93Excellent
Estimated from fit model

Qwen 3.5 122B A10B needs ~105.4 GB VRAM. Mac Studio M3 Ultra 256GB has 184.3 GB. With Q4_K_M quantization, expect ~35 tok/s.

Runtime: llama.cppCapacity: RoomyBandwidth: HighStack: StandardBottleneck: Balanced
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Operating mode

Choose the run profile you care about

Interactive favors responsiveness, while light API and scale-out lean harder on serving readiness. The fit stays the same, but the recommendation lens changes.

Current mode

Balanced

Balanced for general local use. Keeps the ranking neutral across personal and serving workflows.

Capabilities:

Select quantization to explore

Q4_K_M (Medium quality) — 105.4 GB, 34.7 tok/s, Runs well
105.4 GB required184.3 GB available
57% VRAM used

Fit status

Runs well

Decode

34.7 tok/s

TTFT

5579 ms

Safe context

131K

Memory

105.4 GB / 184.3 GB

Memory breakdown

Weights74.4 GB
KV Cache2.4 GB
Runtime0.9 GB
Headroom27.6 GB

See how fast it feels

See how fast it feelsQwen 3.5 122B A10B on Mac Studio M3 Ultra 256GB
1st promptCold start — includes initialization
>Write a Python function to sort a list
Here's a Python function that sorts a list using quicksort: def quicksort(arr): if len(arr) <= 1: return arr pivot = arr[len(arr) // 2] left = [x for x in arr if x < pivot] middle = [x for x in arr if x == pivot] right = [x for x in arr if x > pivot] return quicksort(left) + middle + quicksort(right) # Example usage numbers = [3, 6, 8, 10, 1, 2, 1] print(quicksort(numbers)) # [1, 1, 2, 3, 6, 8, 10] The algorithm picks a pivot, partitions the list into smaller, equal, and larger elements, then recursively sorts each partition and concatenates the results.
2nd promptWarm — model ready, no init overhead
>Now add type hints and a docstring
def quicksort(arr: list[int]) -> list[int]: """Sort a list using the quicksort algorithm. Args: arr: List of integers to sort. Returns: A new sorted list. """ if len(arr) <= 1: return arr pivot = arr[len(arr) // 2] left = [x for x in arr if x < pivot] middle = [x for x in arr if x == pivot] right = [x for x in arr if x > pivot] return quicksort(left) + middle + quicksort(right) Added type hints for the input and return type, plus a Google-style docstring.
Estimated: 34.7 tok/s decode · 5.6s TTFT (warm) · 87 tok/s prefill

What limits this setup

This setup is broadly balanced for this model.

Shared-memory contention still exists

The OS, browser, and inference runtime all compete for the same physical memory pool, so real-world headroom is less forgiving than raw capacity suggests.

Best improvement path

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatSRuns well34.7 tok/s3043 ms131K
CodingSRuns well34.7 tok/s5579 ms131K
Agentic CodingSRuns well34.7 tok/s8114 ms131K
ReasoningSRuns well34.7 tok/s6593 ms131K
RAGSRuns well34.7 tok/s10143 ms131K

Quantization options

How Qwen 3.5 122B A10B (122B params) fits at each quantization level on Mac Studio M3 Ultra 256GB (184.3 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
47.6 GB
LowA84
Q3_K_S
3
59.8 GB
LowS85
NVFP4
4
68.3 GB
MediumS86
Q4_K_M
4
74.4 GB
MediumS87
Q5_K_M
5
87.8 GB
HighS88
Q6_K
6
100.0 GB
HighS90
Q8_0Best for your GPU
8
130.5 GB
Very HighS90
F16
16
250.1 GB
MaximumF0

Get started

Copy-paste commands to run Qwen 3.5 122B A10B on your machine.

Run

lms load Qwen3.5-122B-A10B-Instruct && lms server start

Your hardware

More models your Mac Studio M3 Ultra 256GB can run

ModelParamsGradeDecodeCapabilities
👁 Mistral
Devstral 2 123B Instruct
123BS8.1 tok/s

Frequently asked questions

See all results for Mac Studio M3 Ultra 256GBSee all hardware for Qwen 3.5 122B A10B