NVIDIA · 32 GB GDDR7 · 1792 GB/s bandwidth ·
Alibaba · 8.2B · model ctx up to 128K
Yes — the RTX 5090 32GB (32 GB GDDR7) can run Qwen3-8B. At Q4 with the default 8K context it needs ≈ 7.15 GB VRAM (weights 4.51 GB + KV cache 1.64 GB + 1 GB runtime overhead), which fits within 32 GB. Decode at Q4/8K: ≈ 139.1 tok/s (estimated, batch 1). FP16 (≈ 19.04 GB) also fits, at ≈ 38.2 tok/s (estimated). Estimates come from memory-bandwidth math; rows tagged measured override estimates. Relative ranking is more reliable than absolute tok/s. Methodology.
Fit & speed by quant and context
Quant
Context
VRAM needed
Fits?
tok/s (decode)
Q4
4K
6.33 GB
Yes
139.1est.
Q4
8K default
7.15 GB
Yes
139.1est.
Q4
32K
12.07 GB
Yes
139.1est.
FP16
4K
18.22 GB
Yes
38.2est.
FP16
8K default
19.04 GB
Yes
38.2est.
FP16
32K
23.96 GB
Yes
38.2est.
Fits = weights + KV(ctx) + 1 GB overhead ≤ 95% of VRAM. Measured
anchors are context-agnostic; the fit verdict is recomputed per context. A missing tok/s
means the model is far beyond this card (offload-only territory).