Qwen3.8 27B (VLM) at FP8 (E4M3) needs 27.8 GB for its weights and 33.3 GB in total at 8K context with 8 concurrent users. That means it fits on a single H100 SXM5 80GB. Every figure is computed by tokcalc's open-source capacity model.
| GPUs | Total VRAM | VRAM needed | Decode tok/s | Aggregate tok/s | TTFT | Cost / 1M tok | Fits? |
|---|---|---|---|---|---|---|---|
| 1× H100 | 80 GB | 33.3 GB | 117.6 | 1411 | 958.0 ms | $0.4922 | ✓ |
| 2× H100 | 160 GB | 33.3 GB | 199.9 | 4797 | 494.8 ms | $0.2895 | ✓ |
| 4× H100 | 320 GB | 33.3 GB | 399.7 | 19188 | 262.4 ms | $0.1448 | ✓ |
| 8× H100 | 640 GB | 33.3 GB | 799.5 | 76751 | 146.2 ms | $0.0724 | ✓ |
| Context | Concurrent users | KV per request | Fits? |
|---|---|---|---|
| 4K | 124 | 1.07 GB | ✓ fits |
| 8K | 75 | 2.15 GB | ✓ fits |
| 33K | 22 | 8.59 GB | ✓ fits |
| 66K | 11 | 17.18 GB | ✓ fits |
| 131K | 5 | 34.36 GB | ✓ fits |
| GPU | GPUs | Aggregate tok/s | Cost / 1M tok |
|---|---|---|---|
| RTX 5090 32GB | 2× | 2566 | $0.1083 |
| AMD MI300X 192GB | 1× | 2232 | $0.3111 |
| A100 40GB SXM4 | 1× | 652.8 | $0.3830 |
| AMD MI325X 288GB | 1× | 2527 | $0.3847 |
| A100 80GB SXM4 | 1× | 842.3 | $0.3957 |
| Intel Gaudi 3 128GB | 1× | 1390 | $0.3997 |
Yes. Qwen3.8 27B (VLM) at FP8 (E4M3) needs 33.3 GB including the KV cache, and H100 SXM5 80GB has 80 GB — so it fits on a single GPU.
117.6 tokens/sec per stream and 1411 tok/s aggregate with continuous batching at 8 concurrent users. Time to first token is 958.0 ms, and inter-token latency is 8.5 ms.
$0.4922 per 1M output tokens at 1× H100 SXM5 80GB ($2.50/hr). That is the marginal hardware cost — add idle capacity, ops, and egress for the real figure.
27.8 GB for the weights at FP8 (E4M3), plus 5.5 GB of KV cache for 8 concurrent requests at 8K context — 33.3 GB total. Every extra concurrent user at long context costs more, so leave headroom.
It works. Compare $0.4922 per 1M tokens against the alternatives below — the cheapest option that fits the same workload is 4× RTX 3080 10GB at $0.0511, and the fastest is 1× Cerebras CS-3 (WSE-3) at 8423 tok/s.
Same formulas, your context length, concurrency, and quantisation.