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UniversalComputingResearchGPTForCausalLM

Atom2.7m — Hardware Requirements & GPU Compatibility

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Atom2.7m is a 3M-parameter open language model from UniversalComputingResearch. It supports a context window of up to 512 tokens. At BF16 it needs about 0.31 GB of VRAM — see which GPUs and Macs can run it below.

3M params · dense1K contextApache 2.01.9K downloads16 likes
S

Runs great on a 24 GB GPU

Runs from8 GB BF16Best on24 GB BF16 · ~2114 tok/sMacs from8 GB BF16 · ~231 tok/s

Apache 2.0

Reference GPU · RTX 4090 24 GB

Estimates, ±20% · how we estimate

Run Atom2.7m

One recommended way. Every other method, OS and quant is in the step-by-step guide.

Recommended

vLLM
one command · needs vLLM installed
$vllm serve UniversalComputingResearch/Atom2.7m --max-model-len 512

vLLM repo with its own quantisation

Download: Weights on Hugging Face

install, OS, other quants

Other ways

each opens step-by-step

Run in cloud

Fits on RTX 3060 12GB (11 GB headroom) · BF16

Generation speed
~755 tok/s
generation speed
Cost per 1M output tokens
$0.025
per 1M output tokens

How Much VRAM Does Atom2.7m Need?

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

QuantizationVRAM+32KOn RTX 4090 (reference)
0.3 GB—16-bit · bfloat — Brain floating point 16 — preferred for trainingFits: — context · ~2114 tok/s
est.calculated, no published file yet

Selected BF16

Brain floating point 16

0.3GBat 1K context

Weights
0.1 GB
KV cache
0.0 GB
Overhead
0.3 GB

Fits RTX 4090 (reference) · 23.7 GB free · ~2114 tok/s

≥50 tok/s needs ≥24 GB/s · RTX 5090 ~3757, RTX 3090 Ti ~2114

Which Hardware Can Run Atom2.7m?

BF16 · 0.3 GB

Atom2.7m (BF16) requires 0.3 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 1+ GB is recommended. 52 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti. 163 devices with unified memory can run Atom2.7m, including Mac Studio (M3 Ultra, 256GB), Mac Studio (M3 Ultra, 512GB).

By VRAM tier · typical GPUs and Macs at BF16
8 GB · RTX 4060BF16 · 0.3 GB · ~570 tok/s · —8 GB tier →
12 GB · RTX 3060 12GBBF16 · 0.3 GB · ~755 tok/s · —12 GB tier →
16 GB · RTX 5060 Ti 16GBBF16 · 0.3 GB · ~939 tok/s · —16 GB tier →
24 GB · RTX 4090referenceBF16 · 0.3 GB · ~2114 tok/s · —24 GB tier →
Mac 32 GB · Mac Mini M4BF16 · 0.3 GB · ~271 tok/s · —Macs →
Mac 64 GB · Mac Studio M4 MaxBF16 · 0.3 GB · ~1233 tok/s · —Macs →

Specifications

Publisher
UniversalComputingResearch
Parameters
3M
Architecture
GPTForCausalLM
Context Length
512 tokens
Vocabulary Size
4,096
Release Date
2026-06-30
License
Apache 2.0

Frequently Asked Questions

How much VRAM does Atom2.7m need?

Atom2.7m requires 0.3 GB of VRAM at BF16.

VRAM = Weights + KV Cache + Overhead

Weights = 3M × 16 bits ÷ 8 = 0 GB

KV Cache + Overhead ≈ 0.3 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.

VRAM usage by quantization

0.3 GB

Learn more about VRAM estimation →

Can I run Atom2.7m on a Mac?

Yes — MacBook Air 13" M3 (8 GB) and 145 other Macs can run Atom2.7m. Apple Silicon uses unified memory, so the model shares RAM with the system. At BF16 you need at least 0.3 GB of usable unified memory (RAM minus macOS overhead).

Can I run Atom2.7m locally?

Yes — Atom2.7m can run locally on consumer hardware. Popular tools include Ollama, LM Studio, and llama.cpp.

How fast is Atom2.7m?

At BF16, Atom2.7m can reach ~15484 tok/s on AMD Instinct MI350X. On NVIDIA GeForce RTX 4090: ~2114 tok/s. 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 ÷ 0.31 × 0.65 = ~16774 tok/s

Estimated speed at BF16 (0.3 GB)

~16774 tok/s
~2114 tok/s
~16774 tok/s
~15484 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 Atom2.7m?

At BF16, the download is about 0.01 GB.

Which GPUs can run Atom2.7m?

52 consumer GPUs can run Atom2.7m at BF16. Top options include AMD Radeon RX 6700 XT, AMD Radeon RX 6800, AMD Radeon RX 6800 XT. 52 GPUs have plenty of headroom for comfortable inference.

Which devices can run Atom2.7m?

163 devices with unified memory can run Atom2.7m at BF16 (0.3 GB), including AMD Ryzen AI 9 HX 370 (Strix Point) Laptop, ASUS Ascent GX10, Beelink GTR9 Pro (Ryzen AI Max+ 395, 128 GB), Framework Desktop (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.