Kimi K3 (2.8T-A104B) on L40S 48GB (48GB) — VRAM, KV Cache & Throughput
Kimi K3 (2.8T-A104B) (2780B total, 104B active, Multi-head Latent Attention (MLA) MoE) uses 1570.1 GiB of 4-bit weights (Q4_K_M), requiring 1571.49 GiB total at 8K context and 1573.94 GiB at 32K on L40S 48GB (~0.9 tok/s decode).
Recommended Hardware for Current Configuration
Production Launch Commands
llama-server -hf unsloth/Kimi-K3-GGUF:Q4_K_M \ --ctx-size 8192 -ngl 999 --flash-attn
vllm serve moonshotai/Kimi-K3 \ --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 MI325X 256GB (Dedicated Instance) | 2048 GB | $30.40 / hr | $3696.64 / 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) — Kimi K3 (2.8T-A104B)
Engineering Sizing Notes & Optimization Playbook
Quick Hardware Verdict
A single L40S 48GB (48GB) cannot hold 4-bit Kimi K3 (2.8T-A104B) (1571.49 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
Kimi K3 (2.8T-A104B) uses Multi-head Latent Attention (MLA) MoE (2780B total, 104B active per token). Moving from 8K to 32K context expands FP16 KV cache from 0.82 GiB to 3.27 GiB; enabling 8-bit KV cache (llama.cpp -ctk q8_0 -ctv q8_0 or vLLM --kv-cache-dtype fp8) saves 1.64 GiB at 32K (reducing total VRAM to 1572.3 GiB).
VRAM Scaling Across Context Windows (4K to 128K, 4-bit Weights)
Quantization Precision & Memory Matrix — Kimi K3 (2.8T-A104B) @ 8K
| Quantization Format | Weights (GiB) | KV Cache | Total VRAM (GiB) | Decode Speed | Compatibility (L40S 48GB) | Recommended GPU | Data Source |
|---|---|---|---|---|---|---|---|
| Native Weights (BF16 / FP8 / MXFP4 — Lossless) (MXFP4) | 5178.15 GiB | 0.82 GiB | 5179.54 GiB (5561.49 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) | 2750.89 GiB | 0.82 GiB | 2752.28 GiB (2955.24 GB) | ~0.8 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF Q6_K (6-bit — High Precision) (Q6_K) | 2123.04 GiB | 0.82 GiB | 2124.43 GiB (2281.09 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) | 1841.72 GiB | 0.82 GiB | 1843.11 GiB (1979.02 GB) | ~0.8 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) | 1570.1 GiB | 0.82 GiB | 1571.49 GiB (1687.37 GB) | ~0.9 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF IQ4_XS (4.25-bit — Compact) (IQ4_XS) | 1375.79 GiB | 0.82 GiB | 1377.18 GiB (1478.74 GB) | ~1 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
| GGUF Q3_K_M (3-bit — Low VRAM) (Q3_K_M) | 1265.71 GiB | 0.82 GiB | 1267.1 GiB (1360.54 GB) | ~1.1 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) | 890.47 GiB | 0.82 GiB | 891.86 GiB (957.63 GB) | ~1.6 tok/s | Exceeds Available GPU Memory | Multi-GPU Required | Config-derived formula |
Technical Specifications & FAQ
Does Kimi K3 (2.8T-A104B) fit on L40S 48GB (48GB)?
In 4-bit (Q4_K_M) at 8,192 context, Kimi K3 (2.8T-A104B) requires 1571.49 GiB total GPU memory (1570.1 GiB weights + 0.82 GiB KV cache + 0.57 GiB runtime buffers) against 45.6 GiB usable on L40S 48GB, delivering ~0.9 tok/s decode.
How much VRAM does Kimi K3 (2.8T-A104B) need at 32K context?
At 32,768 context tokens, Kimi K3 (2.8T-A104B) (Multi-head Latent Attention (MLA) MoE) allocates 3.27 GiB for KV cache and state, bringing total 4-bit VRAM to 1573.94 GiB (1690.01 GB decimal).