Three Weeks of Running LLMs Locally (A Model-by-Model Comparison)

Because of company security, I couldn't use external APIs, so I tried running all sorts of local models. My setup is a single 4090 GPU.

1. 7B-class models

  • The speed is genuinely fast. It was sufficient for code autocomplete.
  • However, when I feed it long context, it keeps forgetting the earlier parts.

2. 13B-class

  • The quality improves noticeably, but the speed feels less than half.
  • For static tasks like translation or summarization, this tier offered good value.

3. 30B and above

  • Honestly, with a single 4090, it's frustrating. Even when quantized, the token speed is questionable for real-world use.
  • In the end, I felt that using multiple cards or a small model + fine-tuning combo is more realistic.

Overall: Local LLMs seem better suited for 'specific tasks' than as an 'API replacement.' The moment you try to run one model that's good at everything, costs jump sharply.

by 궁금한사람831

7 answers

Agreed. Once you go past 30B, with a single 4090 it’s really just a vibes thing lol.

by 프롬프트장인111 · ▲0

I wish there were some speed numbers. It doesn't say how many t/s it got, so I can't compare. The claim that 7B and 13B feel half as fast is also subjective...

by 데이터덕후755 · ▲0

I'm running a similar setup, and I agree that 13B is the sweet spot for value. When running translation/summarization, the difference from 7B was striking. But with long contexts, 13B forgets just as much—I'm curious whether that's a model issue or some kind of setup issue.

by 무한도전러245 · ▲0