Arc A770 16GB vs RTX 4070 12GB for Local LLMs

The Arc A770 16GB has about 11% more memory bandwidth (560 vs 504 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 11% faster on the Arc A770 16GB. The Arc A770 16GB fits more of the catalog at Q4/8K — 25 vs 18 of 61 models (16 vs 12 GB VRAM). Largest model that fits the Arc A770 16GB but not the RTX 4070 12GB: gpt-oss-20b (21.5B). MSRP is $349 for the Arc A770 16GB vs $599 for the RTX 4070 12GB. 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 Arc A770 16GB posts the higher tok/s in 31 rows vs 9. Methodology.

Spec comparison

	Arc A770 16GB	RTX 4070 12GB
Vendor	Intel	NVIDIA
VRAM	16 GB	12 GB
Memory type	GDDR6	GDDR6X
Memory bandwidth	560 GB/s	504 GB/s
TDP	225 W	200 W
MSRP (list)	$349	$599
Buy	Search Amazon (affiliate)	ASUS Dual GeForce RTX 4070 OC 12GB (affiliate) · More listings

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 A770 16GB tok/s	Arc A770 16GB fits	RTX 4070 12GB tok/s	RTX 4070 12GB fits	Winner
Qwen3-0.6B	0.8	445.5 est.	Yes	400.9 est.	Yes	Arc A770 16GB
gemma-3-1b-it	1.0	356.4 est.	Yes	320.7 est.	Yes	Arc A770 16GB
Llama-3.2-1B-Instruct	1.2	297.0 est.	Yes	267.3 est.	Yes	Arc A770 16GB
Qwen3-30B-A3B	30.5	257.2 est.	No	130.2 est.	No	Arc A770 16GB
Qwen3-Coder-30B-A3B-Instruct	30.5	257.2 est.	No	130.2 est.	No	Arc A770 16GB
Qwen3-30B-A3B-Instruct-2507	30.5	257.2 est.	No	130.2 est.	No	Arc A770 16GB
GLM-4.7-Flash	31.2	246.9 est.	No	125.0 est.	No	Arc A770 16GB
gpt-oss-20b	21.5	99.0 est.	Yes	199.6 est.	No	RTX 4070 12GB
Qwen3-1.7B	2.0	178.2 est.	Yes	160.4 est.	Yes	Arc A770 16GB
Llama-3.2-3B-Instruct	3.2	111.4 est.	Yes	160.7 measured	Yes	RTX 4070 12GB
Phi-4-mini-instruct	3.8	93.8 est.	Yes	84.4 est.	Yes	Arc A770 16GB
Phi-4-mini-reasoning	3.8	93.8 est.	Yes	84.4 est.	Yes	Arc A770 16GB
gemma-3-4b-it	4.3	91.4 est.	Yes	82.2 est.	Yes	Arc A770 16GB
Qwen3-4B-Instruct-2507	4.0	89.1 est.	Yes	80.2 est.	Yes	Arc A770 16GB
Qwen3-4B-Thinking-2507	4.0	89.1 est.	Yes	80.2 est.	Yes	Arc A770 16GB

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 A770 16GB	RTX 4070 12GB
Catalog models that fit	25 of 61	18 of 61
Largest exclusive fit	gpt-oss-20b (21.5B)	—

Arc A770 16GB details → · RTX 4070 12GB details →