Phi-3 Medium 14B GPU Hardware & VRAM Calculator

Microsoft's heavy-hitting small language model, trained on heavily curated high-quality synthetic data and web texts.

Quantization Precision (Bits)INT4 (Quantized)

Lower bits drastically reduce weight footprint but introduce minor accuracy degradation.

Context Length (Tokens)8,192 Tokens

Longer context windows aggressively ingest VRAM during Key-Value matrix caching.

Estimated Minimum VRAM
14 GB

Dynamically aggregated for Phi-3 Medium 14B based on your selected quantization precision and context boundary.

Scroll down for real-time mathematical proof.

📊 Real-Time VRAM Mathematical Formulation & Derivation

How did we arrive at 14 GB? Below is the verified industrial infrastructure forecasting model.

The VRAM Forecasting Equation
Total VRAM = (Model Weights + KV Cache) × System Overhead
VRAM = ((Params × Bits / 8) + (Context / 1024 × 0.5)) × 1.25

1. Input Parameters & Constants Mapping

Model Variables
  • • Params (Model Size): 14 Billion
  • • Bits (Precision): 4-bit (Selected via slider)
Runtime Constants
  • • Context Window: 8,192 Tokens (Selected via slider)
  • • KV Cache Factor: 0.5 GB / 1K Tokens (Empirical baseline)
  • • System Overhead: 1.25 (25%) (CUDA Context & Activation buffer)

2. Step-by-Step Calculation Engine

[Step 1] Compute Model Weights Allocation:

Formula: (Parameters × Bits) / 8 Bytes per GB

➔ (14B × 4) / 8 = 7.00 GB

[Step 2] Compute Key-Value (KV) Cache Matrix Size:

Formula: (Tokens / 1024) × 0.5 GB Baseline

➔ (8192 / 1024) × 0.5 = 4.00 GB

[Step 3] Apply System Overhead Risk Buffer:

Formula: (Weights + KV Cache) × 1.25 CUDA Runtime Multiplier

➔ (7.00GB + 4.00GB) × 1.25 = 13.75 GB

[Final Step] Rounding Ceiling (Ceil):⌈ 13.75 ⌉ = 14 GB

Live Cloud GPU Cost Breakdown

GPU HardwareRequired Cluster SizeCombined VRAMEstimated CostDeployment Link
NVIDIA Blackwell B2001x Node192 GB$4.85/hrRent via RunPod ↗
NVIDIA Hopper H200 141GB1x Node141 GB$2.95/hrRent via RunPod ↗
NVIDIA H100 SXM 80GB1x Node80 GB$2.19/hrRent via RunPod ↗
NVIDIA H100 PCIe 80GB1x Node80 GB$1.75/hrRent via RunPod ↗
NVIDIA A100 SXM 80GB1x Node80 GB$1.35/hrRent via RunPod ↗
NVIDIA A10G 24GB1x Node24 GB$0.79/hrRent via RunPod ↗
NVIDIA L4 24GB1x Node24 GB$0.55/hrRent via RunPod ↗
NVIDIA RTX 4090 24GB1x Node24 GB$0.65/hrRent via RunPod ↗
NVIDIA RTX 3090 24GB1x Node24 GB$0.39/hrRent via RunPod ↗
AMD Instinct MI300X1x Node192 GB$2.65/hrRent via RunPod ↗
NVIDIA RTX 5090 32GB1x Node32 GB$1.58/hrRent via RunPod ↗
NVIDIA H100 NVL 94GB1x Node94 GB$3.19/hrRent via RunPod ↗
NVIDIA L40S 48GB1x Node48 GB$1.90/hrRent via RunPod ↗
NVIDIA RTX 6000 Ada 48GB1x Node48 GB$2.09/hrRent via RunPod ↗
NVIDIA RTX A6000 48GB1x Node48 GB$1.22/hrRent via RunPod ↗
NVIDIA A100 PCIe 80GB1x Node80 GB$1.19/hrRent via RunPod ↗
NVIDIA RTX A5000 24GB1x Node24 GB$0.27/hrRent via RunPod ↗
NVIDIA RTX Pro 6000 96GB1x Node96 GB$2.09/hrRent via RunPod ↗
NVIDIA A40 48GB1x Node48 GB$0.44/hrRent via RunPod ↗
NVIDIA L40 48GB1x Node48 GB$0.69/hrRent via RunPod ↗
NVIDIA A100 PCIe 40GB1x Node40 GB$0.60/hrRent via RunPod ↗
NVIDIA RTX 4000 Ada 24GB1x Node24 GB$0.45/hrRent via RunPod ↗
NVIDIA RTX A4000 16GB1x Node16 GB$0.23/hrRent via RunPod ↗
AMD Instinct MI210 64GB1x Node64 GB$0.75/hrRent via RunPod ↗

Pros & Cons of Phi-3 Medium 14B

PROS
  • Exceptional logical math skillsets
  • Remarkably lightweight footprint
  • Apache 2.0 open commercial license
CONS
  • Lacks broad world-knowledge nuances found in massive parameter datasets

Production Deployment Guide

# Option 1: Quick Local Deployment via Ollamaollama run phi3:14b
# Option 2: High-Throughput Cluster via vLLMpython -m vllm.entrypoints.openai.api_server --model microsoft/Phi-3-medium-128k-instruct