Written by Jakub Rusinowski · Last updated July 21, 2026
Yes, but it is tight
Yes, but it is tight — Cosmos 3 Nano at Q6_K needs about 15.4 GB of the 16 GB usable on RTX 5080 Desktop (16 GB VRAM, 32 GB RAM), leaving only ~0.6 GB before the runtime starts swapping. Expect ~80.9 tok/s (estimated), with room for about 8,192 tokens of context.
Confidence: low · Recommended quantization: Q6_K · Estimated speed: ~80.9 tok/s
| Usable memory for models | 16 GB |
| Memory bandwidth | 960 GB/s |
| Form factor | Desktop |
| Operating system | Windows or Linux |
| Memory upgradeable | Yes |
| Quant | Memory needed | Fits 16 GB? | Max context | Est. speed | Download |
|---|---|---|---|---|---|
| F16 | 34.2 GB | ✗ No | — | — | 32 GB |
| Q8_0 | 19.2 GB | ✗ No | — | — | 17 GB |
| Q6_K | 15.4 GB | ✓ Yes | 8K | ~80.9 tok/s | 13.1 GB |
| Q5_K_M | 13.6 GB | ✓ Yes | 16K | ~89.9 tok/s | 11.3 GB |
| Q4_K_M | 11.9 GB | ✓ Yes | 16K | ~100.4 tok/s | 9.7 GB |
| Q3_K_M | 9.1 GB | ✓ Yes | 16K | ~125.2 tok/s | 6.8 GB |
| Q2_K | 7.5 GB | ✓ Yes | 16K | ~144.9 tok/s | 5.3 GB |
| Variant | Needs at Q4_K_M | Fits? | Est. speed |
|---|---|---|---|
| Cosmos 3 Super | 41.8 GB | ✗ Too large | — |
| Cosmos 3 Nano | 11.9 GB | ✓ Fits | ~100.4 tok/s |
| Cosmos 3 Edge | 4.1 GB | ✓ Fits | ~219.7 tok/s |
Ollama or llama.cpp (CUDA/ROCm) — vLLM if you need concurrent serving
Yes, but it is tight — Cosmos 3 Nano at Q6_K needs about 15.4 GB of the 16 GB usable on RTX 5080 Desktop (16 GB VRAM, 32 GB RAM), leaving only ~0.6 GB before the runtime starts swapping. Expect ~80.9 tok/s (estimated), with room for about 8,192 tokens of context.
Q6_K — it needs about 15.4 GB of the 16 GB available, downloads as roughly 13.1 GB, and runs at an estimated 80.9 tokens/sec with up to 8K of context.
Nothing binding — the model fits with headroom and generates at a usable speed on this hardware.
Ollama or llama.cpp (CUDA/ROCm) — vLLM if you need concurrent serving