Best of Jeff Geerling — September 2025

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   Jeff Geerling·35w

   I regret building this $3000 Pi AI cluster

   A detailed analysis of building a $3000 Raspberry Pi cluster using 10 Compute Blades with CM5 modules, comparing its performance against more expensive alternatives. The cluster achieved 325 Gflops in HPC benchmarks but struggled with AI workloads, delivering only 0.28 tokens per second for large language models. Despite being energy efficient and compact, the Pi cluster offers poor price-to-performance ratio compared to traditional desktop hardware, making it suitable only for niche use cases requiring high node density or physical separation.

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   Article

   Jeff Geerling·33w

   The Emperor Has No Clothes

   The current AI market appears to be in a massive bubble, with trillions in valuations that cannot be justified by future profits. While legitimate use cases for machine learning exist, they're overshadowed by overhyped and overpriced AI products. Hardware capabilities are slowing down just as model training demands increase, creating a concerning disconnect between investment and practical value.

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