DavidAU·GPT-OSS

OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF — Hardware Requirements & GPU Compatibility

ChatCodeReasoning
44.1K downloads 116 likes

Specifications

Publisher
DavidAU
Family
GPT-OSS
Parameters
20B
Release Date
2025-11-30
License
Apache 2.0

Get Started

How Much VRAM Does OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF Need?

Select a quantization to see compatible GPUs below.

QuantizationBitsVRAM
IQ4_NL4.5012.4 GB
Q5_15.5015.1 GB
Q8_08.0022 GB

Which GPUs Can Run OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF?

Q8_0 · 22 GB

OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF (Q8_0) requires 22 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 29+ GB is recommended. 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 OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF?

Q8_0 · 22 GB

21 devices with unified memory can run OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF, including NVIDIA DGX H100, NVIDIA DGX A100 640GB, Mac Mini M4 Pro (24 GB).

Related Models

Frequently Asked Questions

How much VRAM does OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF need?

OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF requires 12.4 GB of VRAM at IQ4_NL, or 22 GB at Q8_0.

VRAM = Weights + KV Cache + Overhead

Weights = 20B × 4.5 bits ÷ 8 = 11.3 GB

KV Cache + Overhead 1.1 GB (at 2K context + ~0.3 GB framework)

VRAM usage by quantization

12.4 GB

Learn more about VRAM estimation →

What's the best quantization for OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF?

For OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF, Q5_1 (15.1 GB) offers the best balance of quality and VRAM usage. Q8_0 (22 GB) provides better quality if you have the VRAM. The smallest option is IQ4_NL at 12.4 GB.

VRAM requirement by quantization

IQ4_NL
12.4 GB
Q5_1
15.1 GB
Q8_0
22.0 GB

★ Recommended — best balance of quality and VRAM usage.

Learn more about quantization →

Can I run OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF on a Mac?

OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF requires at least 12.4 GB at IQ4_NL, 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 OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF locally?

Yes — OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF can run locally on consumer hardware. At IQ4_NL quantization it needs 12.4 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF?

At IQ4_NL, OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF can reach ~236 tok/s on AMD Instinct MI300X. On NVIDIA GeForce RTX 4090: ~53 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 ÷ 12.4 × 0.55 = ~236 tok/s

Estimated speed at IQ4_NL (12.4 GB)

~236 tok/s
~53 tok/s
~176 tok/s
~146 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 OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF?

At IQ4_NL, the download is about 11.25 GB. The full-precision Q8_0 version is 20.00 GB.

Which GPUs can run OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF?

17 consumer GPUs can run OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF at IQ4_NL (12.4 GB). Top options include AMD Radeon RX 7900 XT, AMD Radeon RX 7900 XTX, NVIDIA GeForce RTX 3090, AMD Radeon RX 6800. 6 GPUs have plenty of headroom for comfortable inference.

Which devices can run OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF?

27 devices with unified memory can run OpenAi GPT OSS 20B HERETIC Uncensored NEO Imatrix GGUF at IQ4_NL (12.4 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.