How much GPU memory does Mistral Medium 3.5 128B need?
Mistral Medium 3.5 128B by Mistral AI has 128B parameters. Its weights take 255 GB at 16-bit, 128 GB at 8-bit and 71.8 GB at 4-bit; released in FP8, its files are 134 GB. Each token of a conversation adds 360 KB of KV cache, so a 32K conversation holds 11.8 GB.
Mistral AI · released in FP8
Mistral Medium 3.5 128B at a glance
- Parameters
- 128B
- As released
- 134 GB
- Its FP8 files
- At 16-bit
- 255 GB
- At 4-bit
- 71.8 GB
- NVFP4
- KV cache a token
- 360 KB
- At 16-bit
- Longest context
- 262,144
- Tokens
GPUs needed at each number format
For 1 conversation of 32,768 tokens with a 16-bit KV cache, counting 92% of each GPU's memory as vLLM does. Under each count, the most tokens a second memory allows.
| GPU | Memory | 16-bit | 8-bit | 4-bit |
|---|---|---|---|---|
| L4 | 24 GB | 16 GPUs9 tokens/s | 8 GPUs17 tokens/s | 4 GPUs14 tokens/s |
| GeForce RTX 5090 | 32 GB | 16 GPUs54 tokens/s | 8 GPUs103 tokens/s | 4 GPUs86 tokens/s |
| L40S | 48 GB | 8 GPUs26 tokens/s | 4 GPUs25 tokens/s | 2 GPUs21 tokens/s |
| A100 80GB | 80 GB | 4 GPUs31 tokens/s | 2 GPUs29 tokens/s | 2 GPUs49 tokens/s |
| H100 | 80 GB | 4 GPUs50 tokens/s | 2 GPUs48 tokens/s | 2 GPUs80 tokens/s |
| RTX PRO 6000 Blackwell | 96 GB | 4 GPUs27 tokens/s | 2 GPUs26 tokens/s | 1 GPU21 tokens/s |
| DGX Spark | 128 GB | 4 GPUs4.1 tokens/s | 2 GPUs3.9 tokens/s | 1 GPU3.3 tokens/s |
| H200 | 141 GB | 4 GPUs72 tokens/s | 2 GPUs69 tokens/s | 1 GPU57 tokens/s |
| B200 | 180 GB | 2 GPUs60 tokens/s | 1 GPU57 tokens/s | 1 GPU96 tokens/s |
| Instinct MI300X | 192 GB | 2 GPUs40 tokens/s | 1 GPU38 tokens/s | 1 GPU63 tokens/s |
| Instinct MI325X | 256 GB | 2 GPUs45 tokens/s | 1 GPU43 tokens/s | 1 GPU72 tokens/s |
| Instinct MI355X | 288 GB | 2 GPUs60 tokens/s | 1 GPU57 tokens/s | 1 GPU96 tokens/s |
Models of a similar size
- Llama 3.3 70B70.6B parameters, 39.7 GB at 4-bit
- Llama 4 Scout109B parameters, 61.1 GB at 4-bit
- gpt-oss-120b117B parameters, 65.7 GB at 4-bit
- Mistral Small 4 119B119B parameters, 67.2 GB at 4-bit
- Nemotron 3 Super 120B A12B124B parameters, 69.5 GB at 4-bit
- Qwen3.5 122B A10B125B parameters, 70.4 GB at 4-bit
Questions
- How much VRAM does Mistral Medium 3.5 128B need?
- 255 GB for its weights at 16-bit, 128 GB at 8-bit and 71.8 GB at 4-bit, plus the KV cache: 360 KB for each token, 11.8 GB for a conversation of 32K tokens and 94.5 GB at its longest context of 262,144 tokens. The server also keeps about 8% of each GPU free.
- Can Mistral Medium 3.5 128B run on 1 GPU?
- Yes, at 4-bit: the smallest single GPU here that holds it with a 32K conversation is the RTX PRO 6000 Blackwell.
- How many H100s does Mistral Medium 3.5 128B need?
- With 1 conversation of 32K tokens, 4 H100s at 16-bit and 2 H100s at 4-bit. Each H100 has 80 GB, of which vLLM uses 92% by default.
- Can I run Mistral Medium 3.5 128B on an RTX 5090?
- The RTX 5090 has 32 GB. With a 32K conversation, Mistral Medium 3.5 128B needs 4 GeForce RTX 5090s at 4-bit and 16 GeForce RTX 5090s (2 servers of 8) at 16-bit.
- How fast does Mistral Medium 3.5 128B run?
- At 4-bit on 2 H100s, memory lets 1 conversation get at most 80 tokens a second. Real servers reach part of that ceiling, and each conversation gets less when many run at once.
Sources
Where each fact comes from
- 1Hugging Face: mistralai/Mistral-Medium-3.5-128B
- 2vLLM: Engine arguments (gpu_memory_utilization)
- 3vLLM: Hybrid KV cache manager
- 4vLLM: Parallelism and scaling
- 5NVIDIA: Introducing NVFP4
- 6NVIDIA: L4 specifications
- 7NVIDIA: GeForce RTX 5090 specifications
- 8NVIDIA: L40S specifications
- 9NVIDIA: A100 80GB specifications
- 10NVIDIA: H100 specifications
- 11NVIDIA: RTX PRO 6000 Blackwell specifications
- 12NVIDIA: DGX Spark specifications
- 13NVIDIA: H200 specifications
- 14NVIDIA: B200 specifications
- 15AMD: Instinct MI300X specifications
- 16AMD: Instinct MI325X specifications
- 17AMD: Instinct MI355X specifications