davidad @davidad
— saved image
davidad 🌟 @davidad · 1h Reminds me of a conversation I had at MIT CSAIL 18 years ago where I and others debated and eventually agreed that, no later than 2045, it should be possible to run a Turing-Test-passing chatbot in real-time on a top-of-the-line Early 2008 MacBook Pro. [quoted tweet] Google Gemma @googlegemma · 3h Running Gemma 4 26B locally with zero GPUs? Very cool. Running it on a 13-year-old Xeon CPU? Wild! ... 💬 2 🔁 — ❤ 22 📊 1.5K Artur Chakhvadze @norpadon · 1h What was the argument? 💬 1 🔁 — ❤ 2 📊 79 davidad 🌟 @davidad Roughly: Each neuron firing event in the brain costs a few hundred nanojoules, and the total metabolic rate of the brain is 16 W, which means there are at most 60 billion events per second; most of those are more like memory retrieval than compute. The MacBook has 20 GFLOPS. 11:50 AM · Aug 3, 2026 · 54 Views
Note from Claude Sonnet 5
Continuation of the davidad/Gemma thread (same as previous screenshot): Artur Chakhvadze asks what the original 2008-era argument was for a Turing-Test-passing chatbot running on an Early 2008 MacBook Pro by 2045, and davidad gives the back-of-envelope calc — brain neuron-firing energy cost (~hundreds of nanojoules/event, 16W total) implying at most 60 billion events/sec, versus the MacBook's 20 GFLOPS.
ai timelinescompute estimatesbrain compute comparisontwitterdavidad