Microsoft·Phi·PhiForCausalLM

Phi 1 5 — Hardware Requirements & GPU Compatibility

ChatCode

Phi 1 5 is a 1.4B-parameter open language model from Microsoft in the Phi family. It supports a context window of up to 2,048 tokens. At Q4_K_M it needs about 0.94 GB of VRAM — see which GPUs and Macs can run it below.

60.9K downloads 1.4K likes2K context

Specifications

Publisher
Microsoft
Family
Phi
Parameters
1.4B
Architecture
PhiForCausalLM
Context Length
2,048 tokens
Vocabulary Size
51,200
Release Date
2025-11-24
License
MIT

Get Started

How Much VRAM Does Phi 1 5 Need?

Select a quantization to see compatible GPUs below.

QuantizationBitsVRAM
Q2_K3.400.7 GB
Q3_K_S3.500.7 GB
Q3_K_M3.900.8 GB
Q4_K_M4.800.9 GB
Q5_K_M5.701.1 GB
Q6_K6.601.3 GB
Q8_08.001.6 GB

Which GPUs Can Run Phi 1 5?

Q4_K_M · 0.9 GB

Phi 1 5 (Q4_K_M) requires 0.9 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 2+ GB is recommended. 35 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti.

Which Devices Can Run Phi 1 5?

Q4_K_M · 0.9 GB

33 devices with unified memory can run Phi 1 5, including NVIDIA DGX H100, NVIDIA DGX A100 640GB.

Benchmarks

View all 2

Related Models

Frequently Asked Questions

How much VRAM does Phi 1 5 need?

Phi 1 5 requires 0.9 GB of VRAM at Q4_K_M, or 1.6 GB at Q8_0.

VRAM = Weights + KV Cache + Overhead

Weights = 1.4B × 4.8 bits ÷ 8 = 0.9 GB

VRAM usage by quantization

0.9 GB

Learn more about VRAM estimation →

What's the best quantization for Phi 1 5?

For Phi 1 5, Q4_K_M (0.9 GB) offers the best balance of quality and VRAM usage. Q5_K_S (1.1 GB) provides better quality if you have the VRAM. The smallest option is Q2_K at 0.7 GB.

VRAM requirement by quantization

Q2_K
0.7 GB
Q3_K_L
0.8 GB
Q4_K_S
0.9 GB
Q4_K_M
0.9 GB
Q5_K_M
1.1 GB
Q8_0
1.6 GB

★ Recommended — best balance of quality and VRAM usage.

Learn more about quantization →

Can I run Phi 1 5 on a Mac?

Phi 1 5 requires at least 0.7 GB at Q2_K, which exceeds the unified memory of most consumer Macs. You would need a Mac Studio or Mac Pro with a high-memory configuration.

Can I run Phi 1 5 locally?

Yes — Phi 1 5 can run locally on consumer hardware. At Q4_K_M quantization it needs 0.9 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Phi 1 5?

At Q4_K_M, Phi 1 5 can reach ~3101 tok/s on AMD Instinct MI300X. On NVIDIA GeForce RTX 4090: ~697 tok/s. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.

tok/s = (bandwidth GB/s ÷ model GB) × efficiency

Example: AMD Instinct MI300X5300 ÷ 0.9 × 0.55 = ~3101 tok/s

Estimated speed at Q4_K_M (0.9 GB)

~3101 tok/s
~697 tok/s
~2318 tok/s
~1917 tok/s

Real-world results typically within ±20%. Speed depends on batch size, quantization kernel, and software stack.

Learn more about tok/s estimation →

What's the download size of Phi 1 5?

At Q4_K_M, the download is about 0.85 GB. The full-precision Q8_0 version is 1.42 GB. The smallest option (Q2_K) is 0.60 GB.

Which GPUs can run Phi 1 5?

35 consumer GPUs can run Phi 1 5 at Q4_K_M (0.9 GB). Top options include AMD Radeon RX 6700 XT, AMD Radeon RX 6800, AMD Radeon RX 6800 XT. 35 GPUs have plenty of headroom for comfortable inference.

Which devices can run Phi 1 5?

33 devices with unified memory can run Phi 1 5 at Q4_K_M (0.9 GB), including Mac Mini M4 (16 GB), Mac Mini M4 (32 GB), Mac Mini M4 Pro (24 GB), Mac Mini M4 Pro (48 GB). Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.