llmrun
swiss-aiApertusApertusForCausalLM

Apertus 70B 2509 — Hardware Requirements & GPU Compatibility

Chat

Apertus 70B 2509 is a 70.6B-parameter open language model from swiss-ai in the Apertus family. It supports a context window of up to 65,536 tokens. At Q4_K_M it needs about 43.33 GB of VRAM — see which GPUs and Macs can run it below.

70.6B params · dense66K contextApache 2.070.8K downloads160 likes

Apertus 70B 2509 runs on a 48 GB+ Mac or a workstation GPU

Best local pick → Mac Studio M5 Max (48 GB) · Q4_K_M · 48 GB · ~10 tok/s

Macs from48 GB Q4_K_M · ~10 tok/s

Apache 2.0

Not set up for it?

Reference GPU · RTX 4090 24 GB

Estimates, ±20% · how we estimate

Run Apertus 70B 2509

One recommended way. Every other method, OS and quant is in the step-by-step guide.Each way opens a step-by-step guide for your OS and quant.

Recommended

vLLM
one command · needs vLLM installed
$vllm serve swiss-ai/Apertus-70B-2509 --max-model-len 16384

vLLM repo with its own quantisation

Download: Weights on Hugging Face

install, OS, other quants

Ways to runOther ways

each opens step-by-step

Run in cloud

Runs on H100 (80 GB) (32 GB headroom) · Q4_K_M

Generation speed
~50 tok/s
generation speed
Cost per 1M output tokens
$14.86
per 1M output tokens

How Much VRAM Does Apertus 70B 2509 Need?

Select a quantization level; the listed hardware adheres to it.

QuantizationVRAM+32KOn RTX 4090 (reference)
31.0 GB41.1 GB2-bit · K-quant — 2-bit quantization with K-quant improvementsDoes not fit: needs 35.7 GB
35.4 GB45.5 GB3-bit medium — 3-bit medium quantizationDoes not fit: needs 40.1 GB
43.3 GB53.4 GB4-bit medium — 4-bit medium quantization — most popular sweet spotDoes not fit: needs 48 GB
51.3 GB61.3 GB5-bit medium — 5-bit medium quantization — good quality/size tradeoffDoes not fit: needs 56 GB
59.2 GB69.3 GB6-bit, very good — 6-bit quantization, very good qualityDoes not fit: needs 63.9 GB
71.6 GB81.6 GB8-bit, near-lossless — 8-bit quantization, near-losslessDoes not fit: needs 76.3 GB
142.2 GB152.2 GB16-bit · bfloat — Brain floating point 16 — preferred for trainingDoes not fit: needs 146.9 GB
est.calculated, no published file yet

Selected Q4_K_M

4-bit medium quantization

48.0GBat 16K context

Weights
42.4 GB
KV cache
5.4 GB
Overhead
0.3 GB

Doesn't fit RTX 4090 (reference) · needs 24.0 GB more

≥10 tok/s needs ≥663 GB/s · M3 Ultra ~13, M2 Ultra ~13

Or .

Which Hardware Can Run Apertus 70B 2509?

Q4_K_M · 43.3 GB

Apertus 70B 2509 (Q4_K_M) requires 43.3 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 57+ GB is recommended. Using the full 66K context window can add up to 20.8 GB, bringing total usage to 64.1 GB. No consumer GPU has enough memory. 67 devices with unified memory can run Apertus 70B 2509, including Mac Studio (M3 Ultra, 256GB), Mac Studio (M3 Ultra, 512GB), Mac Pro M2 Ultra (64 GB).

By VRAM tier · typical GPUs and Macs at Q4_K_M
8–16 GB · RTX 4060, RTX 3060 12GB, RTX 5060 Ti 16GBDoesn't fit — smallest quant needs 35.7 GB8 GB tier →12 GB tier →16 GB tier →
24 GB · RTX 4090referenceDoesn't fit — smallest quant needs 35.7 GB24 GB tier →
Mac 32 GB · Mac Mini M4Doesn't fit — smallest quant needs 35.7 GBMacs →
Mac 64 GB · Mac Studio M4 MaxQ4_K_M · 48 GB · ~9 tok/s · 32KMacs →

Alternatives to Apertus 70B 2509

Apertus family · 5 models →

Similar models

6
ModelScoreVRAMtok/sWhy it is similar
Llama 3.3 70B InstructMeta80.051.3 GB—needs > 24 GBsame size
NVIDIA Nemotron 3.5 Bolt 74B A9B BF16NVIDIA—54.2 GB—needs > 24 GBsame size
Qwen2.5 VL 72B InstructAlibaba—49.7 GB—needs > 24 GBsame size
Qwen2 VL 72B InstructAlibaba—49.7 GB—needs > 24 GBsame size
Qwen1.5 72B ChatAlibaba—86.6 GB—needs > 24 GBsame size
CodeLlama 70B Instruct HFMeta—23.2 GB~29same size

Specifications

Publisher
swiss-ai
Family
Apertus
Parameters
70.6B
Architecture
ApertusForCausalLM
Context Length
65,536 tokens
Vocabulary Size
131,072
Release Date
2025-09-02
License
Apache 2.0

Frequently Asked Questions

How much VRAM does Apertus 70B 2509 need?

Apertus 70B 2509 requires 43.3 GB of VRAM at Q4_K_M, or 142.2 GB at BF16. Full 66K context adds up to 20.8 GB (64.1 GB total).

VRAM = Weights + KV Cache + Overhead

Weights = 70.6B × 4.8 bits ÷ 8 = 42.4 GB

KV Cache + Overhead ≈ 0.9 GB (at 2K context + ~0.3 GB framework)

Fit ratings and hardware model lists check this model with room for a 16K-token context, which needs a little more memory.

KV Cache + Overhead ≈ 21.7 GB (at full 66K context)

VRAM usage by quantization

43.3 GB
64.1 GB

Learn more about VRAM estimation →

Can NVIDIA GeForce RTX 5090 run Apertus 70B 2509?

Yes, at Q2_K (31.0 GB) or lower. Higher quantizations like Q3_K_M (35.4 GB) exceed the NVIDIA GeForce RTX 5090's 32 GB.

What's the best quantization for Apertus 70B 2509?

For Apertus 70B 2509, Q4_K_M (43.3 GB) offers the best balance of quality and VRAM usage. Q5_K_M (51.3 GB) provides better quality if you have the VRAM. The smallest option is Q2_K at 31.0 GB.

VRAM requirement by quantization

Q2_K
31.0 GB
Q4_K_M ★
43.3 GB
Q5_K_M
51.3 GB
Q6_K
59.2 GB
Q8_0
71.6 GB
BF16
142.2 GB

★ Recommended — best balance of quality and VRAM usage.

Learn more about quantization →

Can I run Apertus 70B 2509 on a Mac?

Yes — Mac Studio M5 Max (48 GB) and 55 other Macs can run Apertus 70B 2509. Apple Silicon uses unified memory, so the model shares RAM with the system. At Q4_K_M you need at least 43.3 GB of usable unified memory (RAM minus macOS overhead).

Can I run Apertus 70B 2509 locally?

Yes — Apertus 70B 2509 can run locally on consumer hardware. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Apertus 70B 2509?

At Q4_K_M, Apertus 70B 2509 can reach ~111 tok/s on AMD Instinct MI350X. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.

tok/s = (bandwidth GB/s ÷ model GB) × efficiency

Example: NVIDIA B200 → 8000 ÷ 43.3 × 0.65 = ~120 tok/s

Estimated speed at Q4_K_M (43.3 GB)

~120 tok/s
~120 tok/s
~111 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 Apertus 70B 2509?

At Q4_K_M, the download is about 42.36 GB. The full-precision BF16 version is 141.20 GB. The smallest option (Q2_K) is 30.00 GB.

Which GPUs can run Apertus 70B 2509?

No single consumer GPU has enough VRAM to run Apertus 70B 2509 at Q4_K_M (43.3 GB). Multi-GPU or professional hardware is required.

Which devices can run Apertus 70B 2509?

67 devices with unified memory can run Apertus 70B 2509 at Q4_K_M (43.3 GB), including ASUS Ascent GX10, Beelink GTR9 Pro (Ryzen AI Max+ 395, 128 GB), Framework Desktop (Ryzen AI Max+ 395, 128 GB), GMKtec EVO-X2 (Ryzen AI Max+ 395, 128 GB). Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.