It's fine tuned on ChatGPT answers, but the actual underlying model is GPT-J, a 6 billion parameter model. Roughly one twentieth the size of GPT-3, and it's capabilities are about what you'd expect from that number. I installed it, asked a few dozen questions, then uninstalled when I got garbled nonsense in response. (Not just wrong answers, but incoherent noise, repeating chunks of training prompts back to me unrelated to the question, random python code, etc)