DeepSeek V4.1 Flash (552B-A16B) on RTX 3090 (24GB) — VRAM, KV Cache & Throughput

DeepSeek V4.1 Flash (552B-A16B) (552B total, 16B active, Sparse MoE + GQA) uses 311.93 GiB of 4-bit weights (Q4_K_M), requiring 313.12 GiB total at 8K context and 314.99 GiB at 32K on RTX 3090 (~5.6 tok/s decode).

Interactive Sizing Workbench

Full Compatibility Report →
24 GB · 936 GB/s
Exceeds Available GPU Memory
Config-derived formula HF config.json ↗
Memory Allocation Breakdown (GiB) 313.12 GiB (336.21 GB) / 24 GiB (1305%)
Model Weights: 311.93 GiB KV Cache & State: 0.63 GiB Runtime & Activation Buffers: 0.56 GiB System RAM Offload: 0 GiB
Required GPU Memory
313.12 GiB
336.21 GB (decimal)
Usable Hardware Memory
22.8 GiB
24 GB (physical)
Safe Headroom
-290.32 GiB
1305% utilization
Est. Decode Throughput
~5.6 tok/s
16B active params
Est. Prefill Throughput
~1154 tok/s
4K Prompt TTFT: ~3550 ms
Est. Cost / 1M Tokens
$593.25
Sparse MoE + GQA · MIT

Recommended Hardware for Current Configuration

Best Single GPU
Multi-GPU Required
—
Best Value / Used GPU
2x B200 180GB
360GB · ~$80,000
Apple Unified Memory
Mac Studio M3 Ultra 512GB
~$9,500
Cloud From
RunPod · $11.96 / hr
2x B200 180GB

Production Launch Commands

llama.cpp (GGUF)
llama-server -hf unsloth/DeepSeek-V4.1-Flash-1017-GGUF:Q4_K_M \
  --ctx-size 8192 -ngl 999 --flash-attn
vLLM
vllm serve deepseek-ai/DeepSeek-V4.1-Flash-1017 \
  --max-model-len 8192 --gpu-memory-utilization 0.92
Live Token Speed Simulator (TTFT ~3550ms · ~5.6 tok/s)
[DeepSeek V4.1 Flash (552B-A16B) · 313.12 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
~0.5 months
Est. local power: $7.45 / mo
Provider Recommended Instance Total VRAM Hourly Rate Monthly at Selected Hours Billing Mode Deploy
RunPod 2x B200 180GB (Community Cloud) 360 GB $11.96 / hr $1454.34 / mo Per-second Deploy GPU ↗
Vast.ai 2x B200 180GB (Verified Host) 360 GB $15.00 / hr $1824.49 / mo Spot / On-demand Deploy GPU ↗
Vultr ($300 Free Credit*) 8x A100 80GB SXM (Dedicated Instance · $300 Credit*) 640 GB $19.18 / hr $2331.80 / mo Hourly Deploy GPU ↗
Vultr Cloud GPU 8x A100 80GB SXM (Dedicated Instance) 640 GB $19.18 / hr $2331.80 / mo 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) — DeepSeek V4.1 Flash (552B-A16B)

QLoRA (4b) Exceeds Available GPU Memory
315.28 GiB
Model Weights: 311.93 GiB · Gradients + Optimizer: 2.24 GiB · Act: 1.11 GiB
Recommended GPU: 2x B200 180GB (360GB)
LoRA (16b) Exceeds Available GPU Memory
1033.18 GiB
Model Weights: 1028.18 GiB · Gradients + Optimizer: 3.52 GiB · Act: 1.48 GiB
Recommended GPU: 8x H200 141GB SXM (1128GB)
Full BF16 Exceeds Available GPU Memory
4218.14 GiB
Model Weights: 1028.18 GiB · Gradients + Optimizer: 3187.36 GiB · Act: 2.6 GiB
Recommended GPU: Multi-GPU Required

Engineering Sizing Notes & Optimization Playbook

Quick Hardware Verdict

A single RTX 3090 (24GB) cannot hold 4-bit DeepSeek V4.1 Flash (552B-A16B) (313.12 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

DeepSeek V4.1 Flash (552B-A16B) uses Sparse MoE + GQA (552B total, 16B active per token). Moving from 8K to 32K context expands FP16 KV cache from 0.63 GiB to 2.5 GiB; enabling 8-bit KV cache (llama.cpp -ctk q8_0 -ctv q8_0 or vLLM --kv-cache-dtype fp8) saves 1.25 GiB at 32K (reducing total VRAM to 313.74 GiB).

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

DeepSeek V4.1 Flash (552B-A16B) VRAM scaling from 4K to 128K context (4K: 312.8 GiB, 8K: 313.12 GiB, 32K: 314.99 GiB, 128K: 322.49 GiB) 4K 312.8 GiB (KV 0.31 GiB) 8K 313.12 GiB (KV 0.63 GiB) 32K 314.99 GiB (KV 2.5 GiB) 128K 322.49 GiB (KV 10 GiB) RTX 3090 (24GB)
Model weights remain constant while attention KV cache grows with context length and batch size.

Quantization Precision & Memory Matrix — DeepSeek V4.1 Flash (552B-A16B) @ 8K

Quantization Format Weights (GiB) KV Cache Total VRAM (GiB) Decode Speed Compatibility (RTX 3090) Recommended GPU Data Source
Native Weights (BF16 / FP8 / MXFP4 — Lossless) (FP4FP8) 1028.18 GiB 0.63 GiB 1029.37 GiB (1105.28 GB) ~1.8 tok/s Exceeds Available GPU Memory Multi-GPU Required Official checkpoint size
FP8 / GGUF Q8_0 (8-bit — Near-Lossless) (Q8_0) 546.22 GiB 0.63 GiB 547.41 GiB (587.78 GB) ~3.3 tok/s Exceeds Available GPU Memory Multi-GPU Required Config-derived formula
GGUF Q6_K (6-bit — High Precision) (Q6_K) 421.55 GiB 0.63 GiB 422.74 GiB (453.91 GB) ~4.2 tok/s Exceeds Available GPU Memory Multi-GPU Required Config-derived formula
GGUF Q5_K_M (5-bit — Balanced) (Q5_K_M) 365.78 GiB 0.63 GiB 366.97 GiB (394.03 GB) ~4.8 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) 311.93 GiB 0.63 GiB 313.12 GiB (336.21 GB) ~5.6 tok/s Exceeds Available GPU Memory Multi-GPU Required Config-derived formula
GGUF IQ4_XS (4.25-bit — Compact) (IQ4_XS) 273.3 GiB 0.63 GiB 274.49 GiB (294.73 GB) ~6.4 tok/s Exceeds Available GPU Memory Multi-GPU Required Config-derived formula
GGUF Q3_K_M (3-bit — Low VRAM) (Q3_K_M) 251.43 GiB 0.63 GiB 252.62 GiB (271.25 GB) ~6.9 tok/s Exceeds Available GPU Memory Instinct MI355X 288GB (288GB) Config-derived formula
GGUF UD-Q2_K_XL (2-bit — Extreme MoE) (UD-Q2_K_XL) 176.99 GiB 0.63 GiB 178.18 GiB (191.32 GB) ~9.8 tok/s Exceeds Available GPU Memory Instinct MI325X 256GB (256GB) Config-derived formula

Technical Specifications & FAQ

Does DeepSeek V4.1 Flash (552B-A16B) fit on RTX 3090 (24GB)?

In 4-bit (Q4_K_M) at 8,192 context, DeepSeek V4.1 Flash (552B-A16B) requires 313.12 GiB total GPU memory (311.93 GiB weights + 0.63 GiB KV cache + 0.56 GiB runtime buffers) against 22.8 GiB usable on RTX 3090, delivering ~5.6 tok/s decode.

How much VRAM does DeepSeek V4.1 Flash (552B-A16B) need at 32K context?

At 32,768 context tokens, DeepSeek V4.1 Flash (552B-A16B) (Sparse MoE + GQA) allocates 2.5 GiB for KV cache and state, bringing total 4-bit VRAM to 314.99 GiB (338.22 GB decimal).

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