Alibaba·Qwen·Qwen2ForCausalLM

Qwen1.5 0.5B Chat — Hardware Requirements & GPU Compatibility

Chat

Qwen1.5 0.5B Chat is an early-generation small language model from Alibaba's Qwen series with just 620 million parameters. As one of the smallest models in the Qwen family, it was designed to demonstrate that useful conversational ability is possible even at sub-billion parameter scales. This model runs easily on virtually any hardware including CPUs, older GPUs, and even mobile devices. While its capabilities are limited compared to larger Qwen models, it remains a useful option for embedded applications, rapid prototyping, or situations where minimal resource consumption is the top priority.

92.5K downloads 93 likesApr 202433K context

Specifications

Publisher
Alibaba
Family
Qwen
Parameters
620M
Architecture
Qwen2ForCausalLM
Context Length
32,768 tokens
Vocabulary Size
151,936
Release Date
2024-04-30
License
Other

Get Started

How Much VRAM Does Qwen1.5 0.5B Chat Need?

Select a quantization to see compatible GPUs below.

QuantizationBitsVRAM
BF1616.001.7 GB

Which GPUs Can Run Qwen1.5 0.5B Chat?

BF16 · 1.7 GB

Qwen1.5 0.5B Chat (BF16) requires 1.7 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 3+ GB is recommended. Using the full 33K context window can add up to 3.0 GB, bringing total usage to 4.8 GB. 35 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti.

Which Devices Can Run Qwen1.5 0.5B Chat?

BF16 · 1.7 GB

33 devices with unified memory can run Qwen1.5 0.5B Chat, including NVIDIA DGX H100, NVIDIA DGX A100 640GB.

Related Models

Derivatives (1)

Frequently Asked Questions

How much VRAM does Qwen1.5 0.5B Chat need?

Qwen1.5 0.5B Chat requires 1.7 GB of VRAM at BF16. Full 33K context adds up to 3.0 GB (4.8 GB total).

VRAM = Weights + KV Cache + Overhead

Weights = 620M × 16 bits ÷ 8 = 1.2 GB

KV Cache + Overhead 0.5 GB (at 2K context + ~0.3 GB framework)

KV Cache + Overhead 3.6 GB (at full 33K context)

VRAM usage by quantization

1.7 GB
4.8 GB

Learn more about VRAM estimation →

Can I run Qwen1.5 0.5B Chat on a Mac?

Qwen1.5 0.5B Chat requires at least 1.7 GB at BF16, 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 Qwen1.5 0.5B Chat locally?

Yes — Qwen1.5 0.5B Chat can run locally on consumer hardware. At BF16 quantization it needs 1.7 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Qwen1.5 0.5B Chat?

At BF16, Qwen1.5 0.5B Chat can reach ~1675 tok/s on AMD Instinct MI300X. On NVIDIA GeForce RTX 4090: ~377 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 ÷ 1.7 × 0.55 = ~1675 tok/s

Estimated speed at BF16 (1.7 GB)

~1675 tok/s
~377 tok/s
~1252 tok/s
~1036 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 Qwen1.5 0.5B Chat?

At BF16, the download is about 1.24 GB.