Cerebras IPO

Cerebras IPO is the only thing to talk about this week. 🔥

IPO prices at $185/share. Pops nearly 70% right after. The first wafer-scale chip company to make it public — after a 40-year curse killed every prior attempt.

A water-cooler-style convo on what Cerebras actually builds, why a 23 kW wafer is a power and cooling nightmare, why 44 GB of SRAM is both the magic and the wall for LLM inference, and the cursed Trilogy Systems saga that Gene Amdahl tried — and failed — to pull off in 1983.

Why does Cerebras leave the whole wafer intact instead of dicing it? How do they route around defects to harvest ~900K working cores out of ~1M? Why is power delivery vertical, and why does the wafer literally expand a tenth of a millimeter when it heats up? What does the OpenAI deal actually buy — wafers, or tokens? And why does that distinction matter?

Chapters:
 0:00 Cold open: 23 kW per wafer
 0:15 Cerebras IPO day at $185
 2:39 What's a wafer-scale engine
 10:30 Power, cooling, and thermal expansion
 18:12 The 44 GB wall
 26:35 The Trilogy Systems curse
 32:11 Supercomputing → training → inference
 39:36 The OpenAI deal and the Wild West

Relevant reading:
 Vik's Substack post on the Cerebras IPO and OpenAI deal: https://www.viksnewsletter.com/

Follow Chipstrat:
 Newsletter: https://www.chipstrat.com
X: https://x.com/austinsemis

Follow Vik:
 Newsletter: https://www.viksnewsletter.com/
X: https://x.com/vikramskr

Follow Semi Doped:
 Get more of Austin and Vik daily, free!
 Sign up: https://www.semidoped.com/