RTX 4080 Super for Local LLMs: 16GB VRAM Performance Guide

The RTX 4080 Super launched at $999 with 16GB GDDR6X and 736 GB/s memory bandwidth. Sandwiched between the 4070 Ti Super and the 4090, it is a compelling option for local LLM users who want more than 16GB in a future upgrade but need something now.

RTX 4080 Super Specs

SpecRTX 4080 SuperRTX 4090RTX 4070 Ti S
VRAM16 GB GDDR6X24 GB GDDR6X16 GB GDDR6X
Mem Bandwidth736 GB/s1,008 GB/s672 GB/s
MSRP$999$1,599$799
TDP320W450W285W

LLM Benchmark Results

ModelRTX 4080 SuperRTX 4090% Difference
Llama 3.1 8B Q478 tok/s105 tok/s-26%
Qwen3.6 14B Q455 tok/s74 tok/s-26%
DeepSeek-R1 32B Q428 tok/s30 tok/s-7%

For 32B models, the RTX 4080 Super actually comes close to the 4090 because 16GB can still hold most of the model — VRAM becomes the bottleneck, not bandwidth. The full benchmark dataset is at LLMHardware.io's RTX 4080 Super page.

What 16GB VRAM Runs at Q4_K_M

  • Up to 14B: Fully on GPU with large context (32K+)
  • 14B-32B: Partial GPU load, some CPU offload needed
  • 32B: Fits at Q3_K_M or Q4_K_S (slightly lower quality)

RTX 4080 Super vs Used RTX 4090

Used RTX 4090s are available for ~$1,000-$1,100 in 2026. If you can find one in that price range, the extra 8GB VRAM is worth more for LLM workloads than the bandwidth delta. The 4080 Super makes more sense brand new at $999 versus risking a used 4090.

Bottom line: The RTX 4080 Super is a solid LLM card but gets outclassed by the RTX 4090 on VRAM. At new pricing, the $600 gap buys 8GB VRAM that matters for 32B+ models. Buy 4080 Super if 4090 is unavailable at your price point.

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