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principled-intelligenceQwen 3.5Qwen3_5ForCausalLM

Qwen3.5 2B Text Only — Hardware Requirements & GPU Compatibility

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Qwen3.5 2B Text Only is a 1.9B-parameter open language model from principled-intelligence in the Qwen 3.5 family. It supports a context window of up to 262,144 tokens. At BF16 it needs about 4.16 GB of VRAM — see which GPUs and Macs can run it below.

1.9B params · dense262K contextApache 2.0104 downloads3 likes
S

Runs great on a 24 GB GPU

Runs from8 GB BF16 · 256KBest on24 GB BF16 · ~158 tok/s · 256KMacs from8 GB BF16 · ~17 tok/s

Apache 2.0

Reference GPU · RTX 4090 24 GB

Estimates, ±20% · how we estimate

Run Qwen3.5 2B Text Only

One recommended way. Every other method, OS and quant is in the step-by-step guide.

Recommended

vLLM
one command · needs vLLM installed
$vllm serve principled-intelligence/Qwen3.5-2B-text-only --max-model-len 16384

vLLM repo with its own quantisation

Download: Weights on Hugging Face

install, OS, other quants

Other ways

each opens step-by-step

Run in cloud

Fits on RTX 3060 12GB (7 GB headroom) · BF16

Generation speed
~56 tok/s
generation speed
Cost per 1M output tokens
$0.41
per 1M output tokens

How Much VRAM Does Qwen3.5 2B Text Only Need?

Select a quantization level; the listed hardware adheres to it.

QuantizationVRAM+32KOn RTX 4090 (reference)
4.2 GB4.5 GB16-bit · bfloat — Brain floating point 16 — preferred for trainingFits: 256K context · ~158 tok/s
est.calculated, no published file yet

Selected BF16

Brain floating point 16

4.3GBat 16K context

Weights
3.8 GB
KV cache
0.2 GB
Overhead
0.3 GB

Fits RTX 4090 (reference) · 19.7 GB free · ~158 tok/s

≥50 tok/s needs ≥320 GB/s · RTX 5090 ~280, RTX 3090 Ti ~158

Which Hardware Can Run Qwen3.5 2B Text Only?

BF16 · 4.2 GB

Qwen3.5 2B Text Only (BF16) requires 4.2 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 6+ GB is recommended. Using the full 262K context window can add up to 3.1 GB, bringing total usage to 7.3 GB. 52 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti. 163 devices with unified memory can run Qwen3.5 2B Text Only, including Mac Studio (M3 Ultra, 256GB), Mac Studio (M3 Ultra, 512GB), MacBook Air 13" M3 (8 GB).

By VRAM tier · typical GPUs and Macs at BF16
8 GB · RTX 4060BF16 · 4.3 GB · ~43 tok/s · 256K8 GB tier →
12 GB · RTX 3060 12GBBF16 · 4.3 GB · ~56 tok/s · 256K12 GB tier →
16 GB · RTX 5060 Ti 16GBBF16 · 4.3 GB · ~70 tok/s · 256K16 GB tier →
24 GB · RTX 4090referenceBF16 · 4.3 GB · ~158 tok/s · 256K24 GB tier →
Mac 32 GB · Mac Mini M4BF16 · 4.3 GB · ~20 tok/s · 256KMacs →
Mac 64 GB · Mac Studio M4 MaxBF16 · 4.3 GB · ~92 tok/s · 256KMacs →

Alternatives to Qwen3.5 2B Text Only

Qwen 3.5 family · 34 models →

Similar models

6
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JiRackUltra 1BCMSManhattan—1.8 GB~461same size
Gemma 3n E2B IT Litert LmGoogle—3.1 GB~496same size
Llm Jp 3.1 1.8B Instruct4llm-jp—2.2 GB~360same size
Helium 1 2Bkyutai—2 GB~374same size

Specifications

Publisher
principled-intelligence
Family
Qwen 3.5
Parameters
1.9B
Architecture
Qwen3_5ForCausalLM
Context Length
262,144 tokens
Vocabulary Size
248,320
Release Date
2026-03-11
License
Apache 2.0

Frequently Asked Questions

How much VRAM does Qwen3.5 2B Text Only need?

Qwen3.5 2B Text Only requires 4.2 GB of VRAM at BF16. Full 262K context adds up to 3.1 GB (7.3 GB total).

VRAM = Weights + KV Cache + Overhead

Weights = 1.9B × 16 bits ÷ 8 = 3.8 GB

KV Cache + Overhead ≈ 0.4 GB (at 2K context + ~0.3 GB framework)

Fit ratings and hardware model lists check this model with room for a 16K-token context, which needs a little more memory.

KV Cache + Overhead ≈ 3.5 GB (at full 262K context)

VRAM usage by quantization

4.2 GB
7.3 GB

Learn more about VRAM estimation →

Can I run Qwen3.5 2B Text Only on a Mac?

Yes — Mac Mini M2 (8 GB) and 145 other Macs can run Qwen3.5 2B Text Only. Apple Silicon uses unified memory, so the model shares RAM with the system. At BF16 you need at least 4.2 GB of usable unified memory (RAM minus macOS overhead).

Can I run Qwen3.5 2B Text Only locally?

Yes — Qwen3.5 2B Text Only can run locally on consumer hardware. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Qwen3.5 2B Text Only?

At BF16, Qwen3.5 2B Text Only can reach ~1154 tok/s on AMD Instinct MI350X. On NVIDIA GeForce RTX 4090: ~158 tok/s. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.

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

Example: NVIDIA B200 → 8000 ÷ 4.16 × 0.65 = ~1250 tok/s

Estimated speed at BF16 (4.2 GB)

~1250 tok/s
~158 tok/s
~1250 tok/s
~1154 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 Qwen3.5 2B Text Only?

At BF16, the download is about 3.76 GB.

Which GPUs can run Qwen3.5 2B Text Only?

52 consumer GPUs can run Qwen3.5 2B Text Only at BF16. Top options include AMD Radeon RX 6700 XT, AMD Radeon RX 6800, AMD Radeon RX 6800 XT. 52 GPUs have plenty of headroom for comfortable inference.

Which devices can run Qwen3.5 2B Text Only?

163 devices with unified memory can run Qwen3.5 2B Text Only at BF16 (4.2 GB), including AMD Ryzen AI 9 HX 370 (Strix Point) Laptop, ASUS Ascent GX10, Beelink GTR9 Pro (Ryzen AI Max+ 395, 128 GB), Framework Desktop (Ryzen AI Max+ 395, 128 GB). Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.