Can Mixtral 8x7B run on Mac Studio M3 Ultra 256GB?

YES — Runs Great

B61Good
Estimated from fit model

Mixtral 8x7B needs ~59.2 GB VRAM. Mac Studio M3 Ultra 256GB has 184.3 GB. With Q4_K_M quantization, expect ~37 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) 59.2 GB, 40.1 tok/s, Runs well
59.2 GB required184.3 GB available
32% VRAM used

Fit status

Runs well

Decode

40.1 tok/s

TTFT

4833 ms

Safe context

33K

Memory

59.2 GB / 184.3 GB

Memory breakdown

Weights28.7 GB
KV Cache2.0 GB
Runtime0.9 GB
Headroom27.6 GB

See how fast it feels

See how fast it feelsMixtral 8x7B 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: 40.1 tok/s decode · 4.8s TTFT (warm) · 100 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 well37.3 tok/s2834 ms33K
CodingBRuns well37.3 tok/s5195 ms33K
Agentic CodingBRuns well37.3 tok/s7557 ms33K
ReasoningBRuns well37.3 tok/s6140 ms33K
RAGBRuns well37.3 tok/s9446 ms33K

Quantization options

How Mixtral 8x7B (47B params) fits at each quantization level on Mac Studio M3 Ultra 256GB (184.3 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
18.3 GB
LowC53
Q3_K_S
3
23.0 GB
LowC53
NVFP4
4
26.3 GB
MediumC54
Q4_K_M
4
28.7 GB
MediumC54
Q5_K_M
5
33.8 GB
HighC55
Q6_K
6
38.5 GB
HighB55
Q8_0
8
50.3 GB
Very HighB57
F16Best for your GPU
16
96.4 GB
MaximumB62

Get started

Copy-paste commands to run Mixtral 8x7B on your machine.

Run

ollama run mixtral

Upgrade-Optionen

Hardware, die Mixtral 8x7B gut ausführt

Frequently asked questions

Can Mac Studio M3 Ultra 256GB run Mixtral 8x7B?

Yes, Mac Studio M3 Ultra 256GB can run Mixtral 8x7B with a B grade (Runs well). Expected decode speed: 37.3 tok/s.

How much VRAM does Mixtral 8x7B need?

Mixtral 8x7B (47B parameters) requires approximately 59.2 GB of memory with Q4_K_M quantization.

What is the best quantization for Mixtral 8x7B?

The recommended quantization for Mixtral 8x7B is Q4_K_M, which balances quality and memory efficiency.

What speed will Mixtral 8x7B run at on Mac Studio M3 Ultra 256GB?

On Mac Studio M3 Ultra 256GB, Mixtral 8x7B achieves approximately 37.3 tokens per second decode speed with a time-to-first-token of 5195ms using Q4_K_M quantization.

Can Mac Studio M3 Ultra 256GB run Mixtral 8x7B for coding?

For coding workloads, Mixtral 8x7B on Mac Studio M3 Ultra 256GB receives a B grade with 37.3 tok/s and 33K context.

What context window can Mixtral 8x7B use on Mac Studio M3 Ultra 256GB?

On Mac Studio M3 Ultra 256GB, Mixtral 8x7B can safely use up to 33K tokens of context. The model's official context limit is 33K, but available memory constrains the safe maximum.

Is unified memory on Mac Studio M3 Ultra 256GB as fast as VRAM for Mixtral 8x7B?

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 8x7B
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