Will It Run AI

Can Granite 4.1 8B run on Mac Studio M2 Ultra 128GB?

YES — Runs Great

A71Great
Estimated from fit model

Granite 4.1 8B needs ~22.0 GB VRAM. Mac Studio M2 Ultra 128GB has 92.2 GB. With Q4_K_M quantization, expect ~102 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) 22.0 GB, 102.2 tok/s, Runs well
22.0 GB required92.2 GB available
24% VRAM used

Fit status

Runs well

Decode

102.2 tok/s

TTFT

1894 ms

Safe context

131K

Memory

22.0 GB / 92.2 GB

Memory breakdown

Weights4.9 GB
KV Cache2.4 GB
Runtime0.9 GB
Headroom13.8 GB

See how fast it feels

See how fast it feelsGranite 4.1 8B on Mac Studio M2 Ultra 128GB
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: 102.2 tok/s decode · 1.9s TTFT (warm) · 256 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
ChatARuns well102.2 tok/s1033 ms131K
CodingARuns well102.2 tok/s1894 ms131K
Agentic CodingARuns well102.2 tok/s2755 ms131K
ReasoningARuns well102.2 tok/s2238 ms131K
RAGARuns well102.2 tok/s3444 ms131K

Quantization options

How Granite 4.1 8B (8B params) fits at each quantization level on Mac Studio M2 Ultra 128GB (92.2 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
3.1 GB
LowB63
Q3_K_S
3
3.9 GB
LowB63
NVFP4
4
4.5 GB
MediumB63
Q4_K_M
4
4.9 GB
MediumB63
Q5_K_M
5
5.8 GB
HighB63
Q6_K
6
6.6 GB
HighB64
Q8_0
8
8.6 GB
Very HighB64
F16Best for your GPU
16
16.4 GB
MaximumB64

Get started

Copy-paste commands to run Granite 4.1 8B on your machine.

Run

ollama run granite4.1:8b

Your hardware

More models your Mac Studio M2 Ultra 128GB can run

ModelParamsGradeDecodeCapabilities
MistralDevstral 2 123B Instruct123BS6.3 tok/s
AlibabaQwen3-Coder 30B A3B Instruct30.5BS70.2 tok/s
AlibabaQwen 3.5 27B27BS30.4 tok/s
AlibabaQwen 3.6 27B27BS23.1 tok/s
AlibabaQwen 3.5 122B A10B122BS28.9 tok/s

Frequently asked questions

Can Mac Studio M2 Ultra 128GB run Granite 4.1 8B?

Yes, Mac Studio M2 Ultra 128GB can run Granite 4.1 8B with a A grade (Runs well). Expected decode speed: 102.2 tok/s.

How much VRAM does Granite 4.1 8B need?

Granite 4.1 8B (8B parameters) requires approximately 22.0 GB of memory with Q4_K_M quantization.

What is the best quantization for Granite 4.1 8B?

The recommended quantization for Granite 4.1 8B is Q4_K_M, which balances quality and memory efficiency.

What speed will Granite 4.1 8B run at on Mac Studio M2 Ultra 128GB?

On Mac Studio M2 Ultra 128GB, Granite 4.1 8B achieves approximately 102.2 tokens per second decode speed with a time-to-first-token of 1894ms using Q4_K_M quantization.

Can Mac Studio M2 Ultra 128GB run Granite 4.1 8B for coding?

For coding workloads, Granite 4.1 8B on Mac Studio M2 Ultra 128GB receives a A grade with 102.2 tok/s and 131K context.

What context window can Granite 4.1 8B use on Mac Studio M2 Ultra 128GB?

On Mac Studio M2 Ultra 128GB, Granite 4.1 8B can safely use up to 131K tokens of context. The model's official context limit is 131K, but available memory constrains the safe maximum.

Is unified memory on Mac Studio M2 Ultra 128GB as fast as VRAM for Granite 4.1 8B?

Not always. Mac Studio M2 Ultra 128GB can often fit larger models thanks to unified memory, but a discrete GPU with dedicated high-bandwidth VRAM may still decode faster once the model fits. For this combination, the important distinction is capacity versus sustained throughput.

See all results for Mac Studio M2 Ultra 128GBSee all hardware for Granite 4.1 8B
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