Llama 3.3 70B Instruct on B200 180GB (180GB) — VRAM, KV Cache & Throughput

Llama 3.3 70B Instruct (70.55B total, 70.55B active, Dense GQA) uses 39.6 GiB of 4-bit weights (Q4_K_M), requiring 42.67 GiB total at 8K context and 50.17 GiB at 32K on B200 180GB (~112.2 tok/s decode).

Interactive Sizing Workbench

Full Compatibility Report →
180 GB · 8000 GB/s
Fits with Safe Headroom
Measured GGUF shard size HF config.json ↗
Memory Allocation Breakdown (GiB) 42.67 GiB (45.82 GB) / 180 GiB (24%)
Model Weights: 39.6 GiB KV Cache & State: 2.5 GiB Runtime & Activation Buffers: 0.57 GiB System RAM Offload: 0 GiB
Required GPU Memory
42.67 GiB
45.82 GB (decimal)
Usable Hardware Memory
171 GiB
180 GB (physical)
Safe Headroom
+128.33 GiB
24% utilization
Est. Decode Throughput
~112.2 tok/s
70.55B active params
Est. Prefill Throughput
~8292 tok/s
4K Prompt TTFT: ~494 ms
Est. Cost / 1M Tokens
$0.82
Dense GQA · Llama 3.3

Recommended Hardware for Current Configuration

Best Single GPU
A40 48GB (48GB)
~$5,200
Best Value / Used GPU
RTX A6000 (48GB)
~$4,500
Apple Unified Memory
Ryzen AI Max+ 395 128GB
~$1,999
Cloud From
RunPod · $0.33 / hr
1x RTX A6000

Production Launch Commands

llama.cpp (GGUF)
llama-server -hf unsloth/Llama-3.3-70B-Instruct-GGUF:Q4_K_M \
  --ctx-size 8192 -ngl 999 --flash-attn
vLLM
vllm serve meta-llama/Llama-3.3-70B-Instruct \
  --max-model-len 8192 --gpu-memory-utilization 0.92
Live Token Speed Simulator (TTFT ~494ms · ~112.2 tok/s)
[Llama 3.3 70B Instruct · 42.67 GiB] allocated on target GPU. Prefill completed in TTFT window; streaming autoregressive tokens at memory-bandwidth-bound rate...

Cloud GPU Comparison & Rent-vs-Buy TCO

Verified public rates across RunPod, Vast.ai, Vultr, and DigitalOcean.

Verified: 2026-11-04
Purchase break-even
~154.1 months
Est. local power: $6.38 / mo
Provider Recommended Instance Total VRAM Hourly Rate Monthly at Selected Hours Billing Mode Deploy
RunPod 1x RTX A6000 (Community Cloud) 48 GB $0.33 / hr $40.13 / mo Per-second Deploy GPU ↗
Vast.ai 1x A100 80GB SXM (Verified Host · SXM4) 80 GB $0.44 / hr $53.75 / mo Spot / On-demand Deploy GPU ↗
Vultr ($300 Free Credit*) 1x L40S 48GB (Dedicated Instance · $300 Credit*) 48 GB $1.67 / hr $203.19 / mo Hourly Deploy GPU ↗
Vultr Cloud GPU 1x L40S 48GB (Dedicated Instance) 48 GB $1.67 / hr $203.19 / mo Hourly Deploy GPU ↗
DigitalOcean 1x RTX 6000 Ada (Dedicated Instance) 48 GB $1.57 / hr $190.91 / 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) — Llama 3.3 70B Instruct

QLoRA (4b) Fits with Safe Headroom
50.68 GiB
Model Weights: 39.6 GiB · Gradients + Optimizer: 9.88 GiB · Act: 1.2 GiB
Recommended GPU: RTX PRO 6000 Blackwell (96GB)
LoRA (16b) Fits with Safe Headroom
148.55 GiB
Model Weights: 131.41 GiB · Gradients + Optimizer: 15.52 GiB · Act: 1.62 GiB
Recommended GPU: Instinct MI300X 192GB (192GB)
Full BF16 Exceeds Available GPU Memory
541.63 GiB
Model Weights: 131.41 GiB · Gradients + Optimizer: 407.37 GiB · Act: 2.85 GiB
Recommended GPU: 4x B200 180GB (720GB)

Engineering Sizing Notes & Optimization Playbook

Quick Hardware Verdict

B200 180GB (180GB physical, 171 GiB usable) runs 4-bit (Q4_K_M) Llama 3.3 70B Instruct at 8K context using 42.67 GiB with 128.33 GiB of safe headroom (~112.2 tok/s single-stream decode).

KV Cache & Runtime Tuning

Llama 3.3 70B Instruct uses Dense GQA (70.55B total, 70.55B active per token). Moving from 8K to 32K context expands FP16 KV cache from 2.5 GiB to 10 GiB; enabling 8-bit KV cache (llama.cpp -ctk q8_0 -ctv q8_0 or vLLM --kv-cache-dtype fp8) saves 5 GiB at 32K (reducing total VRAM to 45.17 GiB).

VRAM Scaling Across Context Windows (4K to 128K, 4-bit Weights)

Llama 3.3 70B Instruct VRAM scaling from 4K to 128K context (4K: 41.41 GiB, 8K: 42.67 GiB, 32K: 50.17 GiB, 128K: 80.17 GiB) 4K 41.41 GiB (KV 1.25 GiB) 8K 42.67 GiB (KV 2.5 GiB) 32K 50.17 GiB (KV 10 GiB) 128K 80.17 GiB (KV 40 GiB) B200 180GB (180GB)
Model weights remain constant while attention KV cache grows with context length and batch size.

Quantization Precision & Memory Matrix — Llama 3.3 70B Instruct @ 8K

Quantization Format Weights (GiB) KV Cache Total VRAM (GiB) Decode Speed Compatibility (B200 180GB) Recommended GPU Data Source
Native Weights (BF16 / FP8 / MXFP4 — Lossless) (BF16) 131.41 GiB 2.5 GiB 134.48 GiB (144.4 GB) ~36.5 tok/s Fits with Safe Headroom Instinct MI300X 192GB (192GB) Official checkpoint size
FP8 / GGUF Q8_0 (8-bit — Near-Lossless) (Q8_0) 69.83 GiB 2.5 GiB 72.9 GiB (78.28 GB) ~66.6 tok/s Fits with Safe Headroom RTX PRO 6000 Blackwell (96GB) Measured GGUF shard size
GGUF Q6_K (6-bit — High Precision) (Q6_K) 53.91 GiB 2.5 GiB 56.98 GiB (61.18 GB) ~84.8 tok/s Fits with Safe Headroom RTX PRO 6000 Blackwell (96GB) Measured GGUF shard size
GGUF Q5_K_M (5-bit — Balanced) (Q5_K_M) 46.52 GiB 2.5 GiB 49.59 GiB (53.25 GB) ~97 tok/s Fits with Safe Headroom RTX PRO 6000 Blackwell (96GB) Measured GGUF shard size
Q4_K_M / UD-Q4_K_XL / AWQ (4-bit — Recommended) (Q4_K_M) 39.6 GiB 2.5 GiB 42.67 GiB (45.82 GB) ~112.2 tok/s Fits with Safe Headroom A40 48GB (48GB) Measured GGUF shard size
GGUF IQ4_XS (4.25-bit — Compact) (IQ4_XS) 35.33 GiB 2.5 GiB 38.4 GiB (41.23 GB) ~124.2 tok/s Fits with Safe Headroom A40 48GB (48GB) Measured GGUF shard size
GGUF Q3_K_M (3-bit — Low VRAM) (Q3_K_M) 31.91 GiB 2.5 GiB 34.98 GiB (37.56 GB) ~135.9 tok/s Fits with Safe Headroom A40 48GB (48GB) Measured GGUF shard size
GGUF UD-Q2_K_XL (2-bit — Extreme MoE) (UD-Q2_K_XL) 25.11 GiB 2.5 GiB 28.18 GiB (30.26 GB) ~167 tok/s Fits with Safe Headroom Radeon AI PRO R9700 32GB (32GB) Measured GGUF shard size

Technical Specifications & FAQ

Does Llama 3.3 70B Instruct fit on B200 180GB (180GB)?

In 4-bit (Q4_K_M) at 8,192 context, Llama 3.3 70B Instruct requires 42.67 GiB total GPU memory (39.6 GiB weights + 2.5 GiB KV cache + 0.57 GiB runtime buffers) against 171 GiB usable on B200 180GB, delivering ~112.2 tok/s decode.

How much VRAM does Llama 3.3 70B Instruct need at 32K context?

At 32,768 context tokens, Llama 3.3 70B Instruct (Dense GQA) allocates 10 GiB for KV cache and state, bringing total 4-bit VRAM to 50.17 GiB (53.87 GB decimal).

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