GPT-5.6 Sol Ultrafast Acceleration
- GPT-5.6 Sol on Ultrafast mode answers 2,500 HLE questions in 11 hours and 11 minutes.
- Claude Fable 5 takes 78 hours and 27 minutes to arrive at the same conclusions.
- Ultrafast mode achieves comparable accuracy nearly 7× faster.
The Internet’s Verdict: 70% Hyped, 30% Skeptical
Performance Comparison
GPT-5.6 Sol on Ultrafast mode runs 11x faster than Fable 5, and 5x faster than Opus 4.8 on Fast mode.
Forum Voices
Users are excited about the potential of Ultrafast mode, but some are skeptical about the performance and pricing.
I’ve been waiting so long for something amazing to come out of the OpenAI and Cerebras collaboration. In our evaluations, GPT-5.6 Sol on Ultrafast mode answered all 2,500 HLE questions in 11 hours and 11 minutes. Claude Fable 5 needed 78 hours and 27 minutes, more than three days of continuous compute, to arrive at the same conclusions.
However, some users are concerned about the lack of pricing information and the potential downsides of Ultrafast mode.
Unless I have read over it, besides the animation in the intelligence vs speed graph which only mentions internal data and not whether they truly reran the AA suite, there is no actually solid statement on the important aspect of performance. Neither the Cerebras or OpenAI post outright state that this performs exactly the same as regular 5.6 Sol.
The omission of Mimo v2.5-Pro Ultraspeed in the comparison graphs is also a concern for some users.
Conclusion
GPT-5.6 Sol Ultrafast mode has the potential to revolutionize the field of AI, but more information is needed to fully understand its capabilities and limitations.
Focus Keyword: GPT-5.6 Sol
