Arc B580 12GB vs Arc Pro B70 32GB for Local LLMs

The Arc Pro B70 32GB has about 33% more memory bandwidth (608 vs 456 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 33% faster on the Arc Pro B70 32GB. The Arc Pro B70 32GB fits more of the catalog at Q4/8K — 39 vs 18 of 69 models (32 vs 12 GB VRAM). Largest model that fits the Arc Pro B70 32GB but not the Arc B580 12GB: Qwen3.6-35B-A3B (36.0B). MSRP is $249 for the Arc B580 12GB vs $999 for the Arc Pro B70 32GB. 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 (41 shared models), the Arc Pro B70 32GB posts the higher tok/s in 32 rows vs 8. Methodology.

Spec comparison

	Arc B580 12GB	Arc Pro B70 32GB
Vendor	Intel	Intel
VRAM	12 GB	32 GB
Memory type	GDDR6	GDDR6
Memory bandwidth	456 GB/s	608 GB/s
TDP	190 W	225 W
MSRP (list)	$249	$999
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 41 shared models

Model	Params (B)	Arc B580 12GB tok/s	Arc B580 12GB fits	Arc Pro B70 32GB tok/s	Arc Pro B70 32GB fits	Winner
MiniCPM5-1B	1.08	268.7 est.	Yes	358.2 est.	Yes	Arc Pro B70 32GB
Qwen3.5-2B	2.0	145.1 est.	Yes	193.5 est.	Yes	Arc Pro B70 32GB
Qwen3-Coder-Next	79.7	19.6 est.	No	186.8 est.	No	Arc Pro B70 32GB
gpt-oss-20b	21.5	179.9 est.	No	107.5 est.	Yes	Arc B580 12GB
Qwen3-Next-80B-A3B-Instruct	81.3	18.9 est.	No	179.7 est.	No	Arc Pro B70 32GB
DeepSeek-R1-0528-Qwen3-8B-layer-mix-bpw-3.8-mlx	2.3	126.2 est.	Yes	168.2 est.	Yes	Arc Pro B70 32GB
Qwen3.6-35B-A3B	36.0	90.9 est.	No	129.0 est.	Yes	Arc Pro B70 32GB
Qwen3.5-35B-A3B	34.7	97.5 est.	No	129.0 est.	Yes	Arc Pro B70 32GB
GLM-4.7-Flash	31.2	112.6 est.	No	129.0 est.	Yes	Arc Pro B70 32GB
Qwen3-30B-A3B-Instruct-2507	30.5	117.3 est.	No	129.0 est.	Yes	Arc Pro B70 32GB
Nemotron-3-Nano-Omni-30B-A3B-Reasoning-BF16	30.0	129.0 est.	No	129.0 est.	Yes	Tie
Ornith-1.0-35B	35.0	91.2 est.	No	129.0 est.	Yes	Arc Pro B70 32GB
qwen35b-a3b-fable-sft-abliterated	34.7	92.6 est.	No	129.0 est.	Yes	Arc Pro B70 32GB
gemma-4-26B-A4B-it	25.2	128.2 est.	No	101.8 est.	Yes	Arc B580 12GB
Llama-3.2-3B-Instruct	3.2	47.4 measured	Yes	120.9 est.	Yes	Arc Pro B70 32GB

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	Arc Pro B70 32GB
Catalog models that fit	18 of 69	39 of 69
Largest exclusive fit	—	Qwen3.6-35B-A3B (36.0B)

Arc B580 12GB details → · Arc Pro B70 32GB details →