Mistral Medium 3.5 128B VRAM requirements

Mistral Medium 3.5 128B needs about 82.7 GB of VRAM at Q4_K_M with 8K context, so it needs a 96 GB card such as the RTX PRO 6000 Blackwell; a 24 GB card is too small. Mistral Medium 3.5 128B has 127.7B parameters. With the same 8K context and one request it needs 134 GB at FP8 and 265 GB at FP16/BF16. The published weights take 124 GB (FP8). It does not fit on a 24 GB card at Q4_K_M; the smallest setup here that holds it with an 8K context is the Ryzen AI Max+ 395 (128 GB, 96 GB usable).

82.7 GB at Q4_K_M, 8K context, one request

FP8
134 GB
FP16 / BF16
265 GB
Published weights
124 GB
Smallest setup, Q4_K_M
Ryzen AI Max+ 395 (128 GB, 96 GB usable)
Open Mistral Medium 3.5 128B in the calculator

Worked example: Mistral Medium 3.5 128B with 32K tokens

Inputs: Mistral Medium 3.5 128B · Q4_K_M weights · 32,768 tokens of context · one request · FP16 KV cache

Weights (127.7B at Q4_K_M)
72.0 GB
KV cache (352 KB per token)
11.0 GB
Buffers and runtime (0.5 GB + 10%)
8.80 GB
Total
91.8 GB

The smallest setup here that holds it is the Ryzen AI Max+ 395 (128 GB, 96 GB usable), with about 4.25 GB to spare. Change the inputs in the calculator

What makes Mistral Medium 3.5 128B's memory use different

Per token of context it adds 352 KB of FP16 cache; Llama 3.1 70B (70.6B), the nearest-sized model here with plain full attention, adds 320 KB, so Mistral Medium 3.5 128B needs 10% more.

How much VRAM does Mistral Medium 3.5 128B need?

Mistral Medium 3.5 128B needs 82.7 GB at Q4_K_M, 143 GB at Q8_0 and 265 GB at FP16 with 8,192 tokens of context and one request. Each total below is the weights plus the FP16 KV cache and the runtime overhead (0.5 GB plus 10%), and each row opens the calculator with that setting. What the GGUF names mean.

Fine-tuning Mistral Medium 3.5 128B? Mistral Medium 3.5 128B VRAM for LoRA, QLoRA and full training.

Mistral Medium 3.5 128B GGUF files on Hugging Face

The 8 GGUF files llama.cpp picks for Mistral Medium 3.5 128B with -hf <repo>:<QUANT>, with the bytes the Hugging Face file list reported on 2026-09-29. Each total is that file plus the FP16 KV cache and 0.5 GB + 10%, one request. "vs estimate" compares the file with the bits-per-weight size the table above uses.

QuantFileSizevs estimate 8K32K128K
Q2_K unsloth/Mistral-Medium-3.5-128B-GGUF 43.4 GB46,590,698,592 bytes −13% 51.3 GB60.3 GB96.6 GB
Q3_K_M unsloth/Mistral-Medium-3.5-128B-GGUF3 parts 56.5 GB60,619,859,360 bytes −3% 65.6 GB74.7 GB111 GB
IQ4_XS unsloth/Mistral-Medium-3.5-128B-GGUF3 parts 62.5 GB67,124,438,432 bytes −3% 72.3 GB81.4 GB118 GB
Q4_K_M unsloth/Mistral-Medium-3.5-128B-GGUF3 parts 69.8 GB74,897,139,136 bytes −3% 80.3 GB89.3 GB126 GB
Q5_K_M unsloth/Mistral-Medium-3.5-128B-GGUF3 parts 82.3 GB88,316,814,752 bytes −2% 94.0 GB103 GB139 GB
Q6_K unsloth/Mistral-Medium-3.5-128B-GGUF4 parts 95.5 GB102,575,220,288 bytes −2% 109 GB118 GB154 GB
Q8_0 unsloth/Mistral-Medium-3.5-128B-GGUF4 parts 124 GB132,854,425,088 bytes −2% 140 GB149 GB185 GB
BF16 unsloth/Mistral-Medium-3.5-128B-GGUF6 parts 233 GB250,064,250,304 bytes −2% 260 GB269 GB305 GB

GB here is GiB (1024³ bytes), as everywhere on this site; Hugging Face shows the Q4_K_M file as 74.9 GB, in 10⁹ bytes.

Which Mistral Medium 3.5 128B GGUF fits a 16, 24, 32, 48 or 80 GB GPU or a Mac

From the file sizes above: the largest file that fits each machine with an 8K context and 0.5 GB left free, the longest context it then has room for, and the longest context for Q4_K_M (69.8 GB). One request, FP16 KV cache. The Q4_K_M file is 2.20 GB under its bits-per-weight estimate; the estimate tables and the llama-server command on this page count the estimate, so they show less context.

HardwareLargest GGUF, 8KIts longest contextQ4_K_M, longest context
RTX 5060 Ti 16GB None fits — No
RTX 4090 (24 GB) None fits — No
RTX 5090 (32 GB) None fits — No
L40S (48 GB) None fits — No
H100 SXM (80 GB) IQ4_XS, 62.5 GB 26K 5K
M4 Pro Mac (64 GB, 48 GB usable) None fits — No
M4 Max Mac (128 GB, 96 GB usable) Q5_K_M, 82.3 GB 11K 48K

Run Mistral Medium 3.5 128B with llama.cpp

llama-server -hf unsloth/Mistral-Medium-3.5-128B-GGUF:Q4_K_M -c 41984

Q4_K_M/Mistral-Medium-3.5-128B-Q4_K_M-00001-of-00003.gguf, 74.9 GB, from unsloth/Mistral-Medium-3.5-128B-GGUF (checked 2026-09-29). -c 41984 is the longest Q4_K_M context on the Ryzen AI Max+ 395 (128 GB, 96 GB usable).

Mistral Medium 3.5 128B at 8K, 32K, 128K and 256K (full) tokens of context

All 88 layers use full attention. Each extra token of context adds 352 KB of FP16 cache per request. The last column is the smallest setup here, one card or a group, that holds it at Q4_K_M. How the KV cache works.

ContextKV cache, FP16Total at Q4_K_MTotal at Q8_0Smallest setup, Q4_K_M
8K tokens 2.75 GB 82.7 GB 143 GB Ryzen AI Max+ 395 (128 GB, 96 GB usable)
32K tokens 11.0 GB 91.8 GB 152 GB Ryzen AI Max+ 395 (128 GB, 96 GB usable)
128K tokens 44.0 GB 128 GB 188 GB H200 (141 GB)
256K tokens 88.0 GB 176 GB 236 GB B200 (180 GB)

How fast Mistral Medium 3.5 128B writes

Tokens per second for one request with 8,192 tokens of context, estimated from memory bandwidth. A dash means it does not fit on one card. Try other settings in the speed calculator.

HardwareBandwidthQ4_K_MFP8
RTX 3060 12GB 360 GB/s ——
RTX 4090 1,008 GB/s ——
RTX 5090 1,792 GB/s ——
M4 Max Mac (128 GB) 546 GB/s 3.7–5.1—
M3 Ultra Mac Studio (512 GB) 819 GB/s 5.6–7.63.4–4.7
H100 SXM 3,350 GB/s ——
H200 4,800 GB/s 31–4420–27

Longest context on one GPU

How many tokens of context Mistral Medium 3.5 128B fits on a single card with one request, an FP16 KV cache and 0.5 GB left free. "Full" means the model's whole context window fits.

GPUMemoryQ4_K_MQ8_0FP8
RTX 3060 12 GB NoNoNo
RTX 4060 Ti 16GB 16 GB NoNoNo
RTX 3090 / 4090 24 GB NoNoNo
RTX 5090 32 GB NoNoNo
A100 40GB 40 GB NoNoNo
Mac, 64 GB unified memory 48 GB NoNoNo
L40S / RTX 6000 Ada 48 GB NoNoNo
A100 / H100 80GB 80 GB NoNoNo
Mac, 128 GB unified memory 96 GB 41KNoNo
H200 141 GB 160K2K24K
B200 180 GB 256K (full)105K127K

Model details

Parameters
127.7B (127,704,210,176)
Layers
All 88 layers use full attention
Attention cache
8 KV heads × 128
Context length
262,144 tokens
Published weights
124 GB (FP8)
On Hugging Face
mistralai/Mistral-Medium-3.5-128B
Reported benchmarks
None published in the model card for GPQA, MMLU-Pro or LiveCodeBench.

Why this estimate looks this way

At Q4_K_M and an 8K-token context, Mistral Medium 3.5 128B uses 72.0 GB for weights, 2.75 GB for its FP16 KV cache and 7.97 GB for estimated runtime overhead, totaling 82.7 GB. The overhead is a 0.5 GB base plus 10% of weights and cache.

The architecture and published checkpoint size come from the model's config.json and weight files. These are estimates rather than measured peak memory; inference engines can reserve extra buffers or preallocate the full configured cache.

Mistral Medium 3.5 128B next to similar-sized models

The three models here closest to it in parameter count, at Q4_K_M with 8,192 tokens of context.

ModelParametersTotalKV per tokenSmallest setup
Mistral Medium 3.5 128B 127.7B 82.7 GB 352 KB Ryzen AI Max+ 395 (128 GB, 96 GB usable)
Qwen3.5 122B-A10B 125.1B, 10B active 78.2 GB 24 KB A100 80GB
Nemotron 3.5 Super VL 120B-A12B 124.5B, 12B active 77.7 GB 8 KB A100 80GB
Nemotron 3 Super 120B-A12B 123.6B, 12B active 77.2 GB 8 KB A100 80GB

Mistral Medium 3.5 128B VRAM questions

How much VRAM do I need to run Mistral Medium 3.5 128B locally?

About 82.7 GB at Q4_K_M with an 8K context and one request, by the bits-per-weight estimate, and 265 GB at BF16. The Q4_K_M GGUF Q4_K_M/Mistral-Medium-3.5-128B-Q4_K_M-00001-of-00003.gguf in unsloth/Mistral-Medium-3.5-128B-GGUF is 74,897,139,136 bytes (69.8 GB); with an 8K context it needs 80.3 GB. The smallest setup listed here that holds Q4_K_M is the Ryzen AI Max+ 395 (128 GB, 96 GB usable).

Can I run Mistral Medium 3.5 128B on a 24 GB GPU?

No. The RTX 4090 (24 GB) alone cannot hold it: the smallest listed GGUF, Q2_K at 43.4 GB, needs 51.3 GB with an 8K context.

Which quantization of Mistral Medium 3.5 128B fits in 16 GB of VRAM?

The RTX 5060 Ti 16GB alone cannot hold it: the smallest listed GGUF, Q2_K at 43.4 GB, needs 51.3 GB with an 8K context.

Can I run Mistral Medium 3.5 128B on a Mac?

The M4 Pro Mac (64 GB, 48 GB usable) alone cannot hold it: the smallest listed GGUF, Q2_K at 43.4 GB, needs 51.3 GB with an 8K context. On the M4 Max Mac (128 GB, 96 GB usable), the largest listed GGUF that fits with an 8K context and 0.5 GB free is Q5_K_M (82.3 GB), with up to 11K tokens of context. Q4_K_M (69.8 GB) runs with up to 48K tokens of context. By default macOS lets the GPU use about 75% of unified memory.

How much more VRAM does Mistral Medium 3.5 128B need for 32K or 128K tokens of context?

Its FP16 KV cache is 2.75 GB at 8K, 11.0 GB at 32K, 44.0 GB at 128K for one request, so 128K adds 41.3 GB over 8K, plus 10% overhead. A q8_0 cache (-ctk q8_0 -ctv q8_0) takes 23.4 GB at 128K.

Why does Mistral Medium 3.5 128B use more VRAM than its GGUF file size?

The file holds only the weights. At Q4_K_M with an 8K context: 69.8 GB of weights (the file's 74,897,139,136 bytes) + 2.75 GB of FP16 KV cache + 7.75 GB of compute buffers and runtime (0.5 GB + 10%) = 80.3 GB.

Badge for your model card

Paste it into a Hugging Face or GitHub README; it shows the Q4_K_M total above and links to this page. Q8_0 and FP16 badges.

Mistral Medium 3.5 128B VRAM: 82.7 GB at Q4_K_M, 8K context

Numbers read from the model files on Hugging Face on . Compare it with other models in the reproducible model and GPU report.