Can OpenChat 7B run on MacBook Pro M3 Max 48GB?

Q: Is unified memory on MacBook Pro M3 Max 48GB as fast as VRAM for OpenChat 7B?

Not always. MacBook Pro M3 Max 48GB 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.

YES — Runs Great

C50Usable

Estimated from fit model

OpenChat 7B needs ~12.3 GB VRAM. MacBook Pro M3 Max 48GB has 34.6 GB. With Q4_K_M quantization, expect ~56 tok/s.

Runtime: llama.cppCapacity: RoomyBandwidth: LowStack: StandardBottleneck: Balanced

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) — 12.3 GB, 60.4 tok/s, Runs well

12.3 GB required34.6 GB available

36% VRAM used

Fit status

Runs well

Decode

60.4 tok/s

TTFT

3204 ms

Safe context

Memory

12.3 GB / 34.6 GB

Memory breakdown

Weights4.3 GB

KV Cache2.0 GB

Runtime0.9 GB

Headroom5.2 GB

See how fast it feels

See how fast it feelsOpenChat 7B on MacBook Pro M3 Max 48GB
1st promptCold start — includes initialization
>What is local AI inference?
Local AI inference means running an AI language model directly on your own hardware — your laptop, desktop, or server — instead of sending requests to a remote cloud API.

When you run inference locally the model weights are loaded into your GPU or unified memory. Each token you generate requires reading those weights from memory, so memory bandwidth is the main bottleneck for decode speed.

Key benefits of running locally:
  - Full privacy: your prompts never leave your machine
  - No per-token cost or rate limits
  - Works offline once the model is downloaded
  - Latency depends only on your hardware
2nd promptWarm — model ready, no init overhead
>How much VRAM do I need?
It depends on the model size and quantization level. A rough rule of thumb:

  Model size     Q4 (4-bit)    Q8 (8-bit)    FP16
  7B params      ~4.3 GB       ~7.5 GB       ~14 GB
  13B params     ~7.9 GB       ~13.9 GB      ~26 GB
  70B params     ~42.7 GB      ~74.9 GB      ~140 GB

Most people use 4-bit quantization (Q4_K_M) which gives 90-95% of full quality at a fraction of the memory. A 24 GB GPU can comfortably run most 7B-13B models.
Estimated: 60.4 tok/s decode · 3.2s TTFT (warm) · 151 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

Workload	Grade	Fit	Decode	TTFT	Context
Chat	C	Runs well	60.4 tok/s	1748 ms	8K
Coding	C	Runs well	56.2 tok/s	3444 ms	8K
Agentic Coding	C	Runs well	60.4 tok/s	4661 ms	8K
Reasoning	C	Runs well	60.4 tok/s	3787 ms	8K
RAG	C	Runs well	60.4 tok/s	5826 ms	8K

Quantization options

How OpenChat 7B (7B params) fits at each quantization level on MacBook Pro M3 Max 48GB (34.6 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	2.7 GB	Low	C45
Q3_K_S	3	3.4 GB	Low	C45
NVFP4	4

Get started

Copy-paste commands to run OpenChat 7B on your machine.

Run

ollama run openchat

Upgrade options

Hardware that runs OpenChat 7B well

Mac Studio M2 Ultra 64GBBudget pick

64 GB Unified (+16)800 GB/s (+400)

Raises estimated decode speed by about 62%.98 tok/s decode

Raises estimated decode speed by about 62%.

Adds memory headroom for longer context windows and future model growth.

~$3,999 MSRP

MacBook Pro M4 Max 64GBBest value

64 GB Unified (+16)546 GB/s (+146)

Raises estimated decode speed by about 56%.94.4 tok/s decode

Raises estimated decode speed by about 56%.

Adds memory headroom for longer context windows and future model growth.

~$3,999 MSRP

Mac Studio M1 Ultra 64GBApple upgrade

64 GB Unified (+16)800 GB/s (+400)

Raises estimated decode speed by about 62%.98 tok/s decode

Raises estimated decode speed by about 62%.

Adds memory headroom for longer context windows and future model growth.

~$3,999 MSRP

Frequently asked questions

Can MacBook Pro M3 Max 48GB run OpenChat 7B?

Yes, MacBook Pro M3 Max 48GB can run OpenChat 7B with a C grade (Runs well). Expected decode speed: 56.2 tok/s.

How much VRAM does OpenChat 7B need?

OpenChat 7B (7B parameters) requires approximately 12.3 GB of memory with Q4_K_M quantization.

What is the best quantization for OpenChat 7B?

The recommended quantization for OpenChat 7B is Q4_K_M, which balances quality and memory efficiency.

What speed will OpenChat 7B run at on MacBook Pro M3 Max 48GB?

On MacBook Pro M3 Max 48GB, OpenChat 7B achieves approximately 56.2 tokens per second decode speed with a time-to-first-token of 3444ms using Q4_K_M quantization.

Can MacBook Pro M3 Max 48GB run OpenChat 7B for coding?

For coding workloads, OpenChat 7B on MacBook Pro M3 Max 48GB receives a C grade with 56.2 tok/s and 8K context.

What context window can OpenChat 7B use on MacBook Pro M3 Max 48GB?

On MacBook Pro M3 Max 48GB, OpenChat 7B can safely use up to 8K tokens of context. The model's official context limit is 8K, but available memory constrains the safe maximum.

Is unified memory on MacBook Pro M3 Max 48GB as fast as VRAM for OpenChat 7B?

See all results for MacBook Pro M3 Max 48GB See all hardware for OpenChat 7B

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