Arc B570 10GB vs RTX 4080 Super 16GB for Local LLMs
The RTX 4080 Super 16GB has about 94% more memory bandwidth (736 vs 380 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 94% faster on the RTX 4080 Super 16GB. The RTX 4080 Super 16GB fits more of the catalog at Q4/8K — 25 vs 17 of 61 models (16 vs 10 GB VRAM). Largest model that fits the RTX 4080 Super 16GB but not the Arc B570 10GB: gpt-oss-20b (21.5B). MSRP is $219 for the Arc B570 10GB vs $999 for the RTX 4080 Super 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 (38 shared models), the RTX 4080 Super 16GB posts the higher tok/s in 31 rows vs 7. Methodology.