license: apache-2.0
language:
- en
tags:
- llama
- pretrained
- from-scratch
- gpuburnout
pipeline_tag: text-generation
GPUburnout-3B-75K
A 3.12 billion parameter Llama-style decoder-only transformer, pretrained from scratch as the Season 4 model in the GPUburnout blog series. Final pretraining checkpoint at 75,000 steps.
This is the base model, before any instruction tuning. For the chat-tuned versions, see GPUburnout/GPUburnout-3B-75K-Chat (the shipped SFT champion).
Model Details
- Architecture: Llama-style decoder-only transformer
- Parameters: 3.12B
- Hidden size: 2,560
- Intermediate size: 10,240
- Layers: 32
- Attention heads: 40 query, 10 key/value (GQA)
- Head dim: 64
- Vocab size: 32,005
- Max position: 2,048
- Tie word embeddings: True
- Precision: float16
Training
- Steps: 75,000
- Final val loss: 2.2475
- Training cost: ~$425 (RunPod A100/H200)
- Pretraining data mix: FineWeb-Edu, FineMath, Stack-Edu-Python, PubMed abstracts
- Optimizer: 8-bit AdamW
- Hardware: Mixed A100 SXM 80GB and H200 NVL across training run
Benchmarks (0-shot, float16)
| Benchmark | Score |
|---|---|
| TruthfulQA MC2 | 47.61% |
| HellaSwag (acc_norm) | 28.30% |
| ARC-Easy (acc_norm) | 43.06% |
| ARC-Challenge (acc_norm) | 21.84% |
| MMLU (5-shot acc) | 23.02% |
These are typical small-model-on-limited-tokens numbers. The model has not seen enough data to develop deep academic knowledge (MMLU is near random). It absorbed enough factual content for ARC-Easy to land ~2x random and for TruthfulQA to score above random on calibrated truthfulness, which is the strongest signal at this scale.
Related Models
- GPUburnout/GPUburnout-3B-75K-Chat - SFT champion (step 1500, lr=5e-5, r=16)
- GPUburnout/GPUburnout-3B-75K-Chat-step3000 - Alternative SFT checkpoint (lowest val loss, not shipped)
- GPUburnout/GPUburnout-3B-checkpoints - Intermediate pretraining checkpoints
Blog
This model is part of the GPUburnout LLM-from-scratch blog series. Season 4 documents the 3B build, including the platform pivot from Thunder to RunPod, MooseFS storage debugging, and the 75K-step pretraining run.
License
Apache 2.0. Free to use, modify, redistribute. Attribution appreciated.