01.AI·Yi 1.5·LlamaForCausalLM

Yi 1.5 34B Chat — Hardware Requirements & GPU Compatibility

Chat

Yi 1.5 34B Chat is a 34.4-billion parameter instruction-tuned model by 01.AI, the Chinese AI lab founded by Kai-Fu Lee. It is a bilingual model with strong performance in both English and Chinese, making it particularly well suited for users who need high-quality generation in either language. Yi 1.5 represents an improved iteration of the Yi model family with enhanced reasoning and coding ability. The 34B size requires a GPU with at least 24GB of VRAM for quantized inference, placing it within reach of high-end consumer cards like the RTX 4090. Released under the Yi License.

12.2K downloads 274 likes4K context

Specifications

Publisher
01.AI
Family
Yi 1.5
Parameters
34.4B
Architecture
LlamaForCausalLM
Context Length
4,096 tokens
Vocabulary Size
64,000
License
Apache 2.0

Get Started

How Much VRAM Does Yi 1.5 34B Chat Need?

Select a quantization to see compatible GPUs below.

QuantizationBitsVRAM
IQ2_M2.7012.4 GB
IQ3_XS3.3015.0 GB
IQ3_S3.4015.4 GB
Q2_K3.4015.4 GB
Q3_K_S3.5015.8 GB
IQ3_M3.6016.3 GB
Q3_K_M3.9017.6 GB
Q4_04.0018 GB
Q3_K_L4.1018.4 GB
IQ4_XS4.3019.3 GB
IQ4_NL4.5020.1 GB
Q4_K_S4.5020.1 GB
Q4_K_M4.8021.4 GB
Q5_05.0022.3 GB
Q5_K_S5.5024.4 GB
Q5_K_M5.7025.3 GB
Q6_K6.6029.2 GB
Q8_08.0035.2 GB

Which GPUs Can Run Yi 1.5 34B Chat?

Q4_K_M · 21.4 GB

Yi 1.5 34B Chat (Q4_K_M) requires 21.4 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 28+ GB is recommended. Using the full 4K context window can add up to 0.5 GB, bringing total usage to 21.9 GB. 5 GPUs can run it, including NVIDIA GeForce RTX 5090.

All compatible consumer-level GPUs are running near their VRAM limit. You may also want to consider professional GPUs (e.g., NVIDIA A100, H100) which offer significantly more VRAM. For more headroom and better throughput, consider a multi-GPU configuration with tensor parallelism (supported by tools like vLLM, llama.cpp, or text-generation-inference).

Which Devices Can Run Yi 1.5 34B Chat?

Q4_K_M · 21.4 GB

21 devices with unified memory can run Yi 1.5 34B Chat, including NVIDIA DGX H100, NVIDIA DGX A100 640GB, Mac Mini M4 Pro (24 GB).

Related Models

Frequently Asked Questions

How much VRAM does Yi 1.5 34B Chat need?

Yi 1.5 34B Chat requires 21.4 GB of VRAM at Q4_K_M, or 35.2 GB at Q8_0.

VRAM = Weights + KV Cache + Overhead

Weights = 34.4B × 4.8 bits ÷ 8 = 20.6 GB

KV Cache + Overhead 0.8 GB (at 2K context + ~0.3 GB framework)

KV Cache + Overhead 1.3 GB (at full 4K context)

VRAM usage by quantization

21.4 GB
21.9 GB

Learn more about VRAM estimation →

Can NVIDIA GeForce RTX 4090 run Yi 1.5 34B Chat?

Yes, at Q5_0 (22.3 GB) or lower. Higher quantizations like Q5_K_S (24.4 GB) exceed the NVIDIA GeForce RTX 4090's 24 GB.

What's the best quantization for Yi 1.5 34B Chat?

For Yi 1.5 34B Chat, Q4_K_M (21.4 GB) offers the best balance of quality and VRAM usage. Q5_0 (22.3 GB) provides better quality if you have the VRAM. The smallest option is IQ2_M at 12.4 GB.

VRAM requirement by quantization

IQ2_M
12.4 GB
Q3_K_S
15.8 GB
IQ4_XS
19.3 GB
Q4_K_M
21.4 GB
Q5_0
22.3 GB
Q8_0
35.2 GB

★ Recommended — best balance of quality and VRAM usage.

Learn more about quantization →

Can I run Yi 1.5 34B Chat on a Mac?

Yi 1.5 34B Chat requires at least 12.4 GB at IQ2_M, 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 Yi 1.5 34B Chat locally?

Yes — Yi 1.5 34B Chat can run locally on consumer hardware. At Q4_K_M quantization it needs 21.4 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Yi 1.5 34B Chat?

At Q4_K_M, Yi 1.5 34B Chat can reach ~136 tok/s on AMD Instinct MI300X. On NVIDIA GeForce RTX 4090: ~31 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 ÷ 21.4 × 0.55 = ~136 tok/s

Estimated speed at Q4_K_M (21.4 GB)

~136 tok/s
~31 tok/s
~102 tok/s
~84 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 Yi 1.5 34B Chat?

At Q4_K_M, the download is about 20.63 GB. The full-precision Q8_0 version is 34.39 GB. The smallest option (IQ2_M) is 11.61 GB.