YC
GPT-4.5 = Big Model Energy | YC Decoded
@ Y Combinator
03/11/25
Takeaways
YC
Y Combinator Cast
03/11/25
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GPT-4.5 is OpenAI's largest and most humanlike model to date, representing a significant step in scaling up unsupervised learning and achieving a deeper understanding of the world and human experience.
YC
Y Combinator Cast
03/11/25
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GPT-4.5 excels at natural conversation, creative tasks, and complex planning, while also hallucinating far less than previous models.
YC
Y Combinator Cast
03/11/25
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Reactions to GPT-4.5 have been muted because its improvements over GPT-4 are seen as relatively incremental, despite this launch being an important milestone for future models.
YC
Y Combinator Cast
03/11/25
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The anticipation for GPT-4.5 built up after the release of GPT-4 in early 2023, but the expected GPT-5 never arrived, leading to speculation about internal projects named 'strawberry' and 'Orion'.
YC
Y Combinator Cast
03/11/25
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OpenAI revealed GPT-4.5 as a model capable of reasoning and systematically thinking through complex problems, clearly surpassing GPT-4 in mathematics, coding, and logical tasks.
YC
Y Combinator Cast
03/11/25
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GPT-4.5 is potentially more than 10 times the size of GPT-4, representing a step forward in both pre-training and post-training processes.
YC
Y Combinator Cast
03/11/25
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According to OpenAI researchers, GPT-4.5 stands out for its emotional intelligence, allowing for deeper conversations and a better understanding of human needs and requests.
YC
Y Combinator Cast
03/11/25
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GPT-4.5 achieves around 61.9% accuracy on benchmarks like simple QA, which evaluates its effectiveness in answering questions, and answers fact-based questions with a 38.4% accuracy rate, significantly reducing hallucination rates to roughly 37%.
YC
Y Combinator Cast
03/11/25
@ Y Combinator
GPT-4.5 is more trustworthy for general inquiries compared to GPT-4, excelling in creative tasks like drafting emails, generating imaginative stories, and telling jokes.
YC
Y Combinator Cast
03/11/25
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In subjective evaluations, GPT-4.5 outperforms earlier models by producing more human-like responses and understanding irony better.
YC
Y Combinator Cast
03/11/25
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Evaluations of GPT-4.5 rely on feedback from human testers to assess its performance in subjective areas like writing quality and emotional intelligence.
YC
Y Combinator Cast
03/11/25
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Despite its advancements, GPT-4.5 is significantly more expensive than previous models, costing 30 times more per input token and 15 times more per output token.
YC
Y Combinator Cast
03/11/25
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The high costs associated with GPT-4.5 make it unsuitable for many users at this time.
YC
Y Combinator Cast
03/11/25
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GPT-4.5 shows that scaling unsupervised learning continues to yield valuable improvements in accuracy, emotional intelligence, and creativity, even if these gains are now more incremental than before.
YC
Y Combinator Cast
03/11/25
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The era of scaling pre-training may not be completely over, but reasoning now appears to offer the most potential for maximizing gains from scaling compute.
YC
Y Combinator Cast
03/11/25
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Sam Altman has suggested that unsupervised pre-training models like GPT-4.5 and specialized reasoning-focused models will converge into a unified architecture, which we might see in GPT-5.
YC
Y Combinator Cast
03/11/25
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Reasoning is expected to be a core capability of future models, and the two paradigms of unsupervised pre-training and specialized reasoning complement each other well.
YC
Y Combinator Cast
03/11/25
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A model that combines the knowledge and intuition of GPT-4.5 with advanced reasoning capabilities would be exceptionally powerful, making GPT-4.5 a crucial bridge towards that future.
YC
Y Combinator Cast
03/11/25
@ Y Combinator
Future AI models could blend vast world knowledge, creative fluency, emotional nuance, and advanced reasoning all in one, which is incredibly exciting.
YC
Y Combinator Cast
03/11/25
@ Y Combinator
The era of choosing between broad understanding and powerful reasoning may soon come to an end, as GPT-4.5 provides a glimpse into a future where AI systems combine the best of both paradigms.
YC
Y Combinator Cast
03/11/25
@ Y Combinator
YC is hosting its first-ever AI Startup School in San Francisco on June 16th and 17th, featuring top AI experts and founders who will teach attendees how to build the future.
YC
Y Combinator Cast
03/11/25
@ Y Combinator
The conference is free for computer science graduate students, undergraduates, and new graduates in AI and AI research, and will even cover travel to San Francisco, but applicants must apply as space is limited.