RTX 4070 12GB vs T4 16GB for Local LLMs

The RTX 4070 12GB has about 57% more memory bandwidth (504 vs 320 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 57% faster on the RTX 4070 12GB. The T4 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 T4 16GB but not the RTX 4070 12GB: gpt-oss-20b (21.5B). MSRP is $599 for the RTX 4070 12GB vs $2,000 for the T4 16GB. 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 RTX 4070 12GB posts the higher tok/s in 25 rows vs 15. Methodology.

Spec comparison

	RTX 4070 12GB	T4 16GB
Vendor	NVIDIA	NVIDIA
VRAM	12 GB	16 GB
Memory type	GDDR6X	GDDR6
Memory bandwidth	504 GB/s	320 GB/s
TDP	200 W	70 W
MSRP (list)	$599	$2,000
Buy	ASUS Dual GeForce RTX 4070 OC 12GB (affiliate) · More listings	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)	RTX 4070 12GB tok/s	RTX 4070 12GB fits	T4 16GB tok/s	T4 16GB fits	Winner
Qwen3-0.6B	0.8	400.9 est.	Yes	254.5 est.	Yes	RTX 4070 12GB
gemma-3-1b-it	1.0	320.7 est.	Yes	203.6 est.	Yes	RTX 4070 12GB
Llama-3.2-1B-Instruct	1.2	267.3 est.	Yes	169.7 est.	Yes	RTX 4070 12GB
gpt-oss-20b	21.5	199.6 est.	No	56.6 est.	Yes	RTX 4070 12GB
Llama-3.2-3B-Instruct	3.2	160.7 measured	Yes	63.6 est.	Yes	RTX 4070 12GB
Qwen3-1.7B	2.0	160.4 est.	Yes	101.8 est.	Yes	RTX 4070 12GB
Qwen3-30B-A3B	30.5	130.2 est.	No	147.0 est.	No	T4 16GB
Qwen3-Coder-30B-A3B-Instruct	30.5	130.2 est.	No	147.0 est.	No	T4 16GB
Qwen3-30B-A3B-Instruct-2507	30.5	130.2 est.	No	147.0 est.	No	T4 16GB
GLM-4.7-Flash	31.2	125.0 est.	No	141.1 est.	No	T4 16GB
Phi-4-mini-instruct	3.8	84.4 est.	Yes	53.6 est.	Yes	RTX 4070 12GB
Phi-4-mini-reasoning	3.8	84.4 est.	Yes	53.6 est.	Yes	RTX 4070 12GB
gemma-3-4b-it	4.3	82.2 est.	Yes	52.2 est.	Yes	RTX 4070 12GB
Qwen3-4B-Instruct-2507	4.0	80.2 est.	Yes	50.9 est.	Yes	RTX 4070 12GB
Qwen3-4B-Thinking-2507	4.0	80.2 est.	Yes	50.9 est.	Yes	RTX 4070 12GB

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

	RTX 4070 12GB	T4 16GB
Catalog models that fit	18 of 61	25 of 61
Largest exclusive fit	—	gpt-oss-20b (21.5B)

RTX 4070 12GB details → · T4 16GB details →