Will It Run AI

Can Mixtral 8x22B run on Mac Studio M3 Ultra 256GB?

YES — Runs Great

B63Good
Estimated from fit model

Mixtral 8x22B needs ~118.0 GB VRAM. Mac Studio M3 Ultra 256GB has 184.3 GB. With Q4_K_M quantization, expect ~14 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) 118.0 GB, 13.5 tok/s, Runs well
118.0 GB required184.3 GB available
64% VRAM used

Fit status

Runs well

Decode

13.5 tok/s

TTFT

14387 ms

Safe context

66K

Memory

118.0 GB / 184.3 GB

Memory breakdown

Weights86.0 GB
KV Cache3.4 GB
Runtime0.9 GB
Headroom27.6 GB

See how fast it feels

See how fast it feelsMixtral 8x22B on Mac Studio M3 Ultra 256GB
1st promptCold start — includes initialization
>Solve: If a train travels at 60 mph for 2.5 hours, how far does it go?
Let me work through this step by step. Given information: - Speed = 60 mph (miles per hour) - Time = 2.5 hours Formula: Distance = Speed x Time Calculation: Distance = 60 mph x 2.5 h = 150 miles The train travels 150 miles. Double-check: at 60 mph the train covers 60 miles each hour. In half an hour it covers 30 miles. So in 2.5 hours: 60 + 60 + 30 = 150 miles. Confirmed.
2nd promptWarm — model ready, no init overhead
>What if the train stops for 20 minutes halfway?
The stop doesn't change the total distance covered while moving, but it affects total trip time. Breakdown: - First half: 1.25 hours at 60 mph = 75 miles - Stop: 20 minutes (no distance) - Second half: 1.25 hours at 60 mph = 75 miles Total distance: 150 miles (same) Total time: 2.5 h + 0.33 h = 2.83 hours Average speed: 150 / 2.83 = 53 mph The distance stays the same but average speed drops to 53 mph because of the stop.
Estimated: 13.5 tok/s decode · 14.4s TTFT (warm) · 34 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
ChatBRuns well13.5 tok/s7847 ms66K
CodingBRuns well13.5 tok/s14387 ms66K
Agentic CodingBRuns well13.5 tok/s20926 ms66K
ReasoningBRuns well13.5 tok/s17003 ms66K
RAGBRuns well13.5 tok/s26158 ms66K

Quantization options

How Mixtral 8x22B (141B params) fits at each quantization level on Mac Studio M3 Ultra 256GB (184.3 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
55.0 GB
LowB56
Q3_K_S
3
69.1 GB
LowB58
NVFP4
4
79.0 GB
MediumB59
Q4_K_M
4
86.0 GB
MediumB60
Q5_K_M
5
101.5 GB
HighB61
Q6_K
6
115.6 GB
HighB61
Q8_0Best for your GPU
8
150.9 GB
Very HighB61
F16
16
289.0 GB
MaximumF0

Get started

Copy-paste commands to run Mixtral 8x22B on your machine.

Run

ollama run mixtral:8x22b

Opciones de mejora

Hardware que ejecuta bien Mixtral 8x22B

Frequently asked questions

Can Mac Studio M3 Ultra 256GB run Mixtral 8x22B?

Yes, Mac Studio M3 Ultra 256GB can run Mixtral 8x22B with a B grade (Runs well). Expected decode speed: 13.5 tok/s.

How much VRAM does Mixtral 8x22B need?

Mixtral 8x22B (141B parameters) requires approximately 118.0 GB of memory with Q4_K_M quantization.

What is the best quantization for Mixtral 8x22B?

The recommended quantization for Mixtral 8x22B is Q4_K_M, which balances quality and memory efficiency.

What speed will Mixtral 8x22B run at on Mac Studio M3 Ultra 256GB?

On Mac Studio M3 Ultra 256GB, Mixtral 8x22B achieves approximately 13.5 tokens per second decode speed with a time-to-first-token of 14387ms using Q4_K_M quantization.

Can Mac Studio M3 Ultra 256GB run Mixtral 8x22B for coding?

For coding workloads, Mixtral 8x22B on Mac Studio M3 Ultra 256GB receives a B grade with 13.5 tok/s and 66K context.

What context window can Mixtral 8x22B use on Mac Studio M3 Ultra 256GB?

On Mac Studio M3 Ultra 256GB, Mixtral 8x22B can safely use up to 66K tokens of context. The model's official context limit is 66K, but available memory constrains the safe maximum.

Is unified memory on Mac Studio M3 Ultra 256GB as fast as VRAM for Mixtral 8x22B?

Not always. Mac Studio M3 Ultra 256GB 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 M3 Ultra 256GBSee all hardware for Mixtral 8x22B
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