Hermes 4 405B — Hardware Requirements & GPU Compatibility
ChatReasoningRoleplay
546 downloads
85 likesSpecifications
- Publisher
- Nous Research
- Family
- Hermes
- Parameters
- 405.9B
- Architecture
- LlamaForCausalLM
- Context Length
- 131,072 tokens
- Vocabulary Size
- 128,256
- Release Date
- 2025-09-02
- License
- Llama 3 Community
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HuggingFace
How Much VRAM Does Hermes 4 405B Need?
Select a quantization to see compatible GPUs below.
| Quantization | Bits | VRAM | + Context | File Size | Quality |
|---|---|---|---|---|---|
| BF16 | 16.00 | 813.1 GB | 879.6 GB | 811.71 GB | Brain floating point 16 — preferred for training |
Which GPUs Can Run Hermes 4 405B?
BF16 · 813.1 GBHermes 4 405B (BF16) requires 813.1 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 1057+ GB is recommended. Using the full 131K context window can add up to 66.6 GB, bringing total usage to 879.6 GB. No single GPU has enough memory — multi-GPU or cluster setups are needed.
Related Models
Frequently Asked Questions
- How much VRAM does Hermes 4 405B need?
Hermes 4 405B requires 813.1 GB of VRAM at BF16. Full 131K context adds up to 66.6 GB (879.6 GB total).
VRAM = Weights + KV Cache + Overhead
Weights = 405.9B × 16 bits ÷ 8 = 811.7 GB
KV Cache + Overhead ≈ 1.4 GB (at 2K context + ~0.3 GB framework)
KV Cache + Overhead ≈ 67.9 GB (at full 131K context)
VRAM usage by quantization
BF16813.1 GBBF16 + full context879.6 GB- Can NVIDIA GeForce RTX 5090 run Hermes 4 405B?
No — Hermes 4 405B requires at least 813.1 GB at BF16, which exceeds the NVIDIA GeForce RTX 5090's 32 GB of VRAM.
- Can I run Hermes 4 405B on a Mac?
Hermes 4 405B requires at least 813.1 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 Hermes 4 405B locally?
Yes — Hermes 4 405B can run locally on consumer hardware. At BF16 quantization it needs 813.1 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.
- What's the download size of Hermes 4 405B?
At BF16, the download is about 811.71 GB.
- Which GPUs can run Hermes 4 405B?
No single consumer GPU has enough VRAM to run Hermes 4 405B at BF16 (813.1 GB). Multi-GPU or professional hardware is required.
- Which devices can run Hermes 4 405B?
Hermes 4 405B requires at least 813.1 GB at BF16, which exceeds the unified memory of most consumer devices. A high-memory Mac Studio, Mac Pro, or multi-GPU desktop setup is recommended.