RTX 3090 24GB vs RTX 4090D 24GB (China) for Local LLMs
The RTX 4090D 24GB (China) has about 8% more memory bandwidth (1,008 vs 936 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 8% faster on the RTX 4090D 24GB (China). Both fit the same number of catalog models at Q4/8K (33 of 61; 24 vs 24 GB VRAM). MSRP is $1,499 for the RTX 3090 24GB vs $1,599 for the RTX 4090D 24GB (China). MSRP is a launch list price, not live retail — Amazon prices move; click through for the current price. Not retail-shoppable: RTX 4090D 24GB (China) (datacenter-class; cloud rental is the realistic way to use it). In the Q4/8K head-to-head below (47 shared models), the RTX 4090D 24GB (China) posts the higher tok/s in 45 rows vs 2. Methodology.