Question 1

Is the Arc B580 12GB or the RTX 3060 12GB better for local LLMs?

Accepted Answer

The Arc B580 12GB has about 27% more memory bandwidth (456 vs 360 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 27% faster on the Arc B580 12GB. Both fit the same number of catalog models at Q4/8K (18 of 61; 12 vs 12 GB VRAM). MSRP is $249 for the Arc B580 12GB vs $329 for the RTX 3060 12GB. MSRP is a launch list price, not live retail — Amazon prices move; click through for the current price.

Question 2

How much faster is the Arc B580 12GB than the RTX 3060 12GB for LLM inference?

Accepted Answer

On memory bandwidth the Arc B580 12GB leads by about 27% (456 vs 360 GB/s), and batch-1 decode tracks bandwidth. In the Q4/8K head-to-head on this page, the Arc B580 12GB wins 38 of 40 shared model rows and the RTX 3060 12GB wins 2.

Question 3

Which can run larger models, the Arc B580 12GB or the RTX 3060 12GB?

Accepted Answer

Neither — both fit 18 of 61 catalog models at Q4/8K (12 vs 12 GB VRAM).

	Arc B580 12GB	RTX 3060 12GB
Vendor	Intel	NVIDIA
VRAM	12 GB	12 GB
Memory type	GDDR6	GDDR6
Memory bandwidth	456 GB/s	360 GB/s
TDP	190 W	170 W
MSRP (list)	$249	$329
Buy	Search Amazon (affiliate)	MSI GeForce RTX 3060 Ventus 2X 12G OC (affiliate) · More listings

Model	Params (B)	Arc B580 12GB tok/s	Arc B580 12GB fits	RTX 3060 12GB tok/s	RTX 3060 12GB fits	Winner
Qwen3-0.6B	0.8	362.7 est.	Yes	286.4 est.	Yes	Arc B580 12GB
gemma-3-1b-it	1.0	290.2 est.	Yes	229.1 est.	Yes	Arc B580 12GB
Llama-3.2-1B-Instruct	1.2	241.8 est.	Yes	190.9 est.	Yes	Arc B580 12GB
gpt-oss-20b	21.5	180.6 est.	No	84.0 measured	No	Arc B580 12GB
Qwen3-1.7B	2.0	145.1 est.	Yes	114.5 est.	Yes	Arc B580 12GB
Llama-3.2-3B-Instruct	3.2	47.4 measured	Yes	122.9 measured	Yes	RTX 3060 12GB
Qwen3-30B-A3B	30.5	117.8 est.	No	93.0 est.	No	Arc B580 12GB
Qwen3-Coder-30B-A3B-Instruct	30.5	117.8 est.	No	93.0 est.	No	Arc B580 12GB
Qwen3-30B-A3B-Instruct-2507	30.5	117.8 est.	No	93.0 est.	No	Arc B580 12GB
GLM-4.7-Flash	31.2	113.1 est.	No	89.3 est.	No	Arc B580 12GB
Phi-4-mini-instruct	3.8	76.4 est.	Yes	60.3 est.	Yes	Arc B580 12GB
Phi-4-mini-reasoning	3.8	76.4 est.	Yes	60.3 est.	Yes	Arc B580 12GB
gemma-3-4b-it	4.3	74.4 est.	Yes	58.7 est.	Yes	Arc B580 12GB
Qwen3-4B-Instruct-2507	4.0	72.5 est.	Yes	57.3 est.	Yes	Arc B580 12GB
Qwen3-4B-Thinking-2507	4.0	72.5 est.	Yes	57.3 est.	Yes	Arc B580 12GB

Arc B580 12GB vs RTX 3060 12GB for Local LLMs

Spec comparison

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

Fit coverage at Q4 / 8K

	Arc B580 12GB	RTX 3060 12GB
Catalog models that fit	18 of 61	18 of 61
Largest exclusive fit	—	—