Qwen3.8 2.4T-A95B on RTX 6000 Ada (48GB) — VRAM, KV Cache & Throughput
Qwen3.8 2.4T-A95B (2400B total, 95B active, Hybrid Linear/Mamba + MoE) uses 1355.88 GiB of 4-bit weights (Q4_K_M), requiring 1357.58 GiB total at 8K context and 1359.74 GiB at 32K on RTX 6000 Ada (~1 tok/s decode).
Recommended Hardware for Current Configuration
Production Launch Commands
llama-server -hf Qwen/Qwen3.8-2.4T-A95B:Q4_K_M \ --ctx-size 8192 -ngl 999 --flash-attn
vllm serve Qwen/Qwen3.8-2.4T-A95B \ --max-model-len 8192 --gpu-memory-utilization 0.92
Cloud GPU Comparison & Rent-vs-Buy TCO
Verified public rates across RunPod, Vast.ai, Vultr, and DigitalOcean.
| Provider | Recommended Instance | Total VRAM | Hourly Rate | Monthly at Selected Hours | Billing Mode | Deploy |
|---|---|---|---|---|---|---|
| RunPod | 8x B300 288GB Blackwell Ultra (Community Cloud) | 2304 GB | $55.52 / hr | $6751.23 / mo | Per-second | Deploy GPU ↗ |
| Vast.ai | — | — | — | — | Spot / On-demand | Deploy GPU ↗ |
| Vultr ($300 Free Credit*) | — | — | — | — | Hourly | Deploy GPU ↗ |
| Vultr Cloud GPU | — | — | — | — | Hourly | Deploy GPU ↗ |
| DigitalOcean | 8x Instinct MI300X 192GB (Dedicated Instance) | 1536 GB | $20.72 / hr | $2519.55 / mo | Per-second | Deploy GPU ↗ |
Rates reflect public listings on the verification date and fluctuate with regional inventory.
Fine-Tuning VRAM Requirements (QLoRA / LoRA / Full) — Qwen3.8 2.4T-A95B
Engineering Sizing Notes & Optimization Playbook
Quick Hardware Verdict
A single RTX 6000 Ada (48GB) cannot hold 4-bit Qwen3.8 2.4T-A95B (1357.58 GiB at 8K) entirely in VRAM. Use multi-GPU tensor parallelism, offload layers to system RAM, or deploy on a larger cloud GPU.
KV Cache & Runtime Tuning
Qwen3.8 2.4T-A95B uses Hybrid Linear/Mamba + MoE (2400B total, 95B active per token). Moving from 8K to 32K context expands FP16 KV cache from 1.13 GiB to 3.29 GiB; enabling 8-bit KV cache (llama.cpp -ctk q8_0 -ctv q8_0 or vLLM --kv-cache-dtype fp8) saves 1.44 GiB at 32K (reducing total VRAM to 1358.3 GiB).
VRAM Scaling Across Context Windows (4K to 128K, 4-bit Weights)
Quantization Precision & Memory Matrix — Qwen3.8 2.4T-A95B @ 8K
| Quantization Format | Weights (GiB) | KV Cache | Total VRAM (GiB) | Decode Speed | Compatibility (RTX 6000 Ada) | Recommended GPU | Data Source |
|---|---|---|---|---|---|---|---|
| Native Weights (BF16 / FP8 / MXFP4 — Lossless) (FP8) | 4470.3 GiB | 1.13 GiB | 4472 GiB (4801.77 GB) | ~0.8 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Official checkpoint size |
| FP8 / GGUF Q8_0 (8-bit — Near-Lossless) (Q8_0) | 2374.87 GiB | 1.13 GiB | 2376.57 GiB (2551.82 GB) | ~0.8 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF Q6_K (6-bit — High Precision) (Q6_K) | 1832.84 GiB | 1.13 GiB | 1834.54 GiB (1969.82 GB) | ~0.8 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF Q5_K_M (5-bit — Balanced) (Q5_K_M) | 1590.18 GiB | 1.13 GiB | 1591.88 GiB (1709.27 GB) | ~0.9 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| Q4_K_M / UD-Q4_K_XL / AWQ (4-bit — Recommended) (Q4_K_M) | 1355.88 GiB | 1.13 GiB | 1357.58 GiB (1457.69 GB) | ~1 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF IQ4_XS (4.25-bit — Compact) (IQ4_XS) | 1188.03 GiB | 1.13 GiB | 1189.73 GiB (1277.46 GB) | ~1.1 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF Q3_K_M (3-bit — Low VRAM) (Q3_K_M) | 1092.96 GiB | 1.13 GiB | 1094.66 GiB (1175.38 GB) | ~1.2 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF UD-Q2_K_XL (2-bit — Extreme MoE) (UD-Q2_K_XL) | 769.17 GiB | 1.13 GiB | 770.87 GiB (827.72 GB) | ~1.7 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
Technical Specifications & FAQ
Does Qwen3.8 2.4T-A95B fit on RTX 6000 Ada (48GB)?
In 4-bit (Q4_K_M) at 8,192 context, Qwen3.8 2.4T-A95B requires 1357.58 GiB total GPU memory (1355.88 GiB weights + 1.13 GiB KV cache + 0.57 GiB runtime buffers) against 45.6 GiB usable on RTX 6000 Ada, delivering ~1 tok/s decode.
How much VRAM does Qwen3.8 2.4T-A95B need at 32K context?
At 32,768 context tokens, Qwen3.8 2.4T-A95B (Hybrid Linear/Mamba + MoE) allocates 3.29 GiB for KV cache and state, bringing total 4-bit VRAM to 1359.74 GiB (1460.01 GB decimal).