Will It Run AI

Can Phi 4 reasoning vision 15B run on Mac Studio M2 Ultra 64GB?

YES — Runs Great

C49Usable
Estimated from fit model

Phi 4 reasoning vision 15B needs ~18.7 GB VRAM. Mac Studio M2 Ultra 64GB has 46.1 GB. With Q4_K_M quantization, expect ~51 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) 18.7 GB, 50.7 tok/s, Runs well
18.7 GB required46.1 GB available
41% VRAM used

Fit status

Runs well

Decode

50.7 tok/s

TTFT

3818 ms

Safe context

265K

Memory

18.7 GB / 46.1 GB

Memory breakdown

Weights9.2 GB
KV Cache1.8 GB
Runtime0.9 GB
Headroom6.9 GB

See how fast it feels

See how fast it feelsPhi 4 reasoning vision 15B on Mac Studio M2 Ultra 64GB
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: 50.7 tok/s decode · 3.8s TTFT (warm) · 127 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
ChatCRuns well50.7 tok/s2082 ms265K
CodingCRuns well50.7 tok/s3818 ms265K
Agentic CodingCRuns well50.7 tok/s5553 ms265K
ReasoningCRuns well50.7 tok/s4512 ms265K
RAGCRuns well50.7 tok/s6941 ms265K

Quantization options

How Phi 4 reasoning vision 15B (15B params) fits at each quantization level on Mac Studio M2 Ultra 64GB (46.1 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
5.9 GB
LowC42
Q3_K_S
3
7.4 GB
LowC42
NVFP4
4
8.4 GB
MediumC43
Q4_K_M
4
9.2 GB
MediumC43
Q5_K_M
5
10.8 GB
HighC43
Q6_K
6
12.3 GB
HighC44
Q8_0
8
16.1 GB
Very HighC45
F16Best for your GPU
16
30.7 GB
MaximumC48

Get started

Copy-paste commands to run Phi 4 reasoning vision 15B on your machine.

Run

lms load hf-jamesburton--phi-4-reasoning-vision-15b-gguf && lms server start

升级选项

能流畅运行 Phi 4 reasoning vision 15B 的硬件

Frequently asked questions

Can Mac Studio M2 Ultra 64GB run Phi 4 reasoning vision 15B?

Yes, Mac Studio M2 Ultra 64GB can run Phi 4 reasoning vision 15B with a C grade (Runs well). Expected decode speed: 50.7 tok/s.

How much VRAM does Phi 4 reasoning vision 15B need?

Phi 4 reasoning vision 15B (15B parameters) requires approximately 18.7 GB of memory with Q4_K_M quantization.

What is the best quantization for Phi 4 reasoning vision 15B?

The recommended quantization for Phi 4 reasoning vision 15B is Q4_K_M, which balances quality and memory efficiency.

What speed will Phi 4 reasoning vision 15B run at on Mac Studio M2 Ultra 64GB?

On Mac Studio M2 Ultra 64GB, Phi 4 reasoning vision 15B achieves approximately 50.7 tokens per second decode speed with a time-to-first-token of 3818ms using Q4_K_M quantization.

Can Mac Studio M2 Ultra 64GB run Phi 4 reasoning vision 15B for coding?

For coding workloads, Phi 4 reasoning vision 15B on Mac Studio M2 Ultra 64GB receives a C grade with 50.7 tok/s and 265K context.

What context window can Phi 4 reasoning vision 15B use on Mac Studio M2 Ultra 64GB?

On Mac Studio M2 Ultra 64GB, Phi 4 reasoning vision 15B can safely use up to 265K tokens of context. The model's official context limit is —, but available memory constrains the safe maximum.

Is unified memory on Mac Studio M2 Ultra 64GB as fast as VRAM for Phi 4 reasoning vision 15B?

Not always. Mac Studio M2 Ultra 64GB 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 64GBSee all hardware for Phi 4 reasoning vision 15B
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