Estimates from memory-bandwidth formula; rows marked "measured" override. Methodology.
Fit & speed by quant and context
Quant
Context
VRAM needed
Fits?
tok/s (decode)
Q4
4K
3.9 GB
Yes
18.9±est.
Q4
8K default
4.55 GB
Yes
18.9±est.
Q4
32K
8.49 GB
No
13.0±est.
FP16
4K
9.66 GB
No
2.8±est.
FP16
8K default
10.31 GB
No
2.4±est.
FP16
32K
14.25 GB
No
1.2±est.
Fits = weights + KV(ctx) + 0.5 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).
VRAM breakdown at 8K context
Quant
Weights
KV cache
Overhead
Total needed
MacBook Neo A18 Pro 8GB VRAM
Q4
2.24 GB
1.31 GB
0.5 GB
4.55 GB
8 GB
FP16
8.0 GB
1.31 GB
0.5 GB
10.31 GB
8 GB
Other GPUs that run NVIDIA-Nemotron-3-Nano-4B-BF16