Looking for fast GPT-4 level LLM usable via API. (not via OpenAI)

Hey, I'm looking for a fast LLM to use via API, that's as good or almost as good as GPT-4, better than GPT-3.5-turbo at least.

GPT-4 via OpenAI is too slow -- 100 token output takes >3 seconds.

Where can I find one?