Mixtral 8x7B (MoE) at FP8 (E4M3) needs 46.7 GB for its weights and 55.3 GB in total at 8K context with 8 concurrent users. That means it needs 2× L40S 48GB. Every figure is computed by tokcalc's open-source capacity model.
L40S 48GB has no NVLink, so 2-way tensor parallelism runs over PCIe. tokcalc applies a flat 0.85× multi-GPU efficiency factor for this, which is realistic for NVLink-equipped datacenter cards but optimistic for PCIe scale-out — treat the throughput and cost figures for this configuration as an upper bound, and measure before committing.
| GPUs | Total VRAM | VRAM needed | Decode tok/s | Aggregate tok/s | TTFT | Cost / 1M tok | Fits? |
|---|---|---|---|---|---|---|---|
| 1× L40S | 48 GB | 55.3 GB | 0.000 | 0.000 | — | — | ✗ |
| 2× L40S | 96 GB | 55.3 GB | 111.0 | 2664 | 2.35 s | $0.1460 | ✓ |
| 4× L40S | 192 GB | 55.3 GB | 222.0 | 10657 | 1.19 s | $0.0730 | ✓ |
| 8× L40S | 384 GB | 55.3 GB | 444.1 | 42629 | 609.1 ms | $0.0365 | ✓ |
| Context | Concurrent users | KV per request | Fits? |
|---|---|---|---|
| 4K | 91 | 549.8 MB | ✓ fits |
| 8K | 45 | 1.07 GB | ✓ fits |
| 33K | 11 | 4.29 GB | ✓ fits |
| 66K | 5 | 8.59 GB | ✓ fits |
| 131K | 2 | 17.18 GB | ✓ fits |
| GPU | GPUs | Aggregate tok/s | Cost / 1M tok |
|---|---|---|---|
| RTX 5090 32GB | 2× | 5526 | $0.0503 |
| AMD MI300X 192GB | 1× | 4807 | $0.1445 |
| AMD MI325X 288GB | 1× | 5442 | $0.1787 |
| A100 80GB SXM4 | 1× | 1814 | $0.1838 |
| Intel Gaudi 3 128GB | 1× | 2993 | $0.1856 |
| H100 SXM5 80GB | 1× | 3038 | $0.2286 |
Yes, but it needs 2× L40S 48GB. At FP8 (E4M3) the total footprint is 55.3 GB (46.7 GB of weights plus 8.6 GB of KV cache at 8K × 8 concurrent users), against 96 GB of available VRAM across 2 GPUs.
111.0 tokens/sec per stream and 2664 tok/s aggregate with continuous batching at 8 concurrent users. Time to first token is 2.35 s, and inter-token latency is 9.0 ms.
$0.1460 per 1M output tokens at 2× L40S 48GB ($0.7000/hr). That is the marginal hardware cost — add idle capacity, ops, and egress for the real figure.
46.7 GB for the weights at FP8 (E4M3), plus 8.6 GB of KV cache for 8 concurrent requests at 8K context — 55.3 GB total. Every extra concurrent user at long context costs more, so leave headroom.
It works. Compare $0.1460 per 1M tokens against the alternatives below — the cheapest option that fits the same workload is 8× RTX 3080 10GB at $0.0119, and the fastest is 2× Cerebras CS-3 (WSE-3) at 61674 tok/s.
Same formulas, your context length, concurrency, and quantisation.