MacBook Pro M3 Max 128GB vs RTX 4090 24GB for Local LLMs
The RTX 4090 24GB has about 152% more memory bandwidth (1,008 vs 400 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 152% faster on the RTX 4090 24GB. The MacBook Pro M3 Max 128GB fits more of the catalog at Q4/8K — 47 vs 33 of 61 models (128 vs 24 GB VRAM). Largest model that fits the MacBook Pro M3 Max 128GB but not the RTX 4090 24GB: DeepSeek-V4-Flash (158.1B). MSRP is $4,199 for the MacBook Pro M3 Max 128GB vs $1,599 for the RTX 4090 24GB. 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 (47 shared models), the RTX 4090 24GB posts the higher tok/s in 44 rows vs 3. Methodology.