Arc B580 12GB vs MacBook Pro M4 Max 128GB for Local LLMs

The MacBook Pro M4 Max 128GB has about 20% more memory bandwidth (546 vs 456 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 20% faster on the MacBook Pro M4 Max 128GB. The MacBook Pro M4 Max 128GB fits more of the catalog at Q4/8K — 47 vs 18 of 61 models (128 vs 12 GB VRAM). Largest model that fits the MacBook Pro M4 Max 128GB but not the Arc B580 12GB: DeepSeek-V4-Flash (158.1B). MSRP is $249 for the Arc B580 12GB vs $4,399 for the MacBook Pro M4 Max 128GB. MSRP is a launch list price, not live retail — Amazon prices move; click through for the current price. In the Q4/8K head-to-head below (40 shared models), the MacBook Pro M4 Max 128GB posts the higher tok/s in 30 rows vs 10. Methodology.

Spec comparison

	Arc B580 12GB	MacBook Pro M4 Max 128GB
Vendor	Intel	Apple
VRAM	12 GB	128 GB
Memory type	GDDR6	LPDDR5X
Memory bandwidth	456 GB/s	546 GB/s
TDP	190 W	160 W
MSRP (list)	$249	$4,399
Buy	Search Amazon (affiliate)	Search Amazon (affiliate)

MSRP is the launch list price, not live retail. Buy links are Amazon affiliate links — the price after you click is the live price.

Q4 / 8K head-to-head — top 15 of 40 shared models

Model	Params (B)	Arc B580 12GB tok/s	Arc B580 12GB fits	MacBook Pro M4 Max 128GB tok/s	MacBook Pro M4 Max 128GB fits	Winner
Qwen3-0.6B	0.8	362.7 est.	Yes	434.3 est.	Yes	MacBook Pro M4 Max 128GB
gemma-3-1b-it	1.0	290.2 est.	Yes	347.5 est.	Yes	MacBook Pro M4 Max 128GB
Llama-3.2-1B-Instruct	1.2	241.8 est.	Yes	289.5 est.	Yes	MacBook Pro M4 Max 128GB
gpt-oss-20b	21.5	180.6 est.	No	96.5 est.	Yes	Arc B580 12GB
Qwen3-1.7B	2.0	145.1 est.	Yes	173.7 est.	Yes	MacBook Pro M4 Max 128GB
Qwen3-30B-A3B	30.5	117.8 est.	No	115.8 est.	Yes	Arc B580 12GB
Qwen3-Coder-30B-A3B-Instruct	30.5	117.8 est.	No	115.8 est.	Yes	Arc B580 12GB
Qwen3-30B-A3B-Instruct-2507	30.5	117.8 est.	No	115.8 est.	Yes	Arc B580 12GB
GLM-4.7-Flash	31.2	113.1 est.	No	115.8 est.	Yes	MacBook Pro M4 Max 128GB
Qwen3-Next-80B-A3B-Instruct	81.3	18.5 est.	No	115.8 est.	Yes	MacBook Pro M4 Max 128GB
Qwen3-Coder-Next	79.7	19.3 est.	No	115.8 est.	Yes	MacBook Pro M4 Max 128GB
Llama-3.2-3B-Instruct	3.2	47.4 measured	Yes	108.6 est.	Yes	MacBook Pro M4 Max 128GB
Phi-4-mini-instruct	3.8	76.4 est.	Yes	91.4 est.	Yes	MacBook Pro M4 Max 128GB
Phi-4-mini-reasoning	3.8	76.4 est.	Yes	91.4 est.	Yes	MacBook Pro M4 Max 128GB
gemma-3-4b-it	4.3	74.4 est.	Yes	89.1 est.	Yes	MacBook Pro M4 Max 128GB

est. = bandwidth-based estimate; measured = curated real benchmark that overrides the estimate. Fits = weights + KV(8K) + 1 GB overhead ≤ 95% of VRAM.

Fit coverage at Q4 / 8K

	Arc B580 12GB	MacBook Pro M4 Max 128GB
Catalog models that fit	18 of 61	47 of 61
Largest exclusive fit	—	DeepSeek-V4-Flash (158.1B)

Arc B580 12GB details → · MacBook Pro M4 Max 128GB details →