When Cerebras unveiled its first Wafer-Scale Engine on August 19, 2019, the chip contained more than 1.2 trillion transistors and 400,000 AI-optimized cores across 46,225 square millimeters of silicon, with 18 gigabytes of on-chip memory. The company called it the largest chip ever built.
The number is striking because a chip is normally cut from a wafer into many small dies; Cerebras kept the whole wafer as one device. For comparison, a high-end GPU of the era held on the order of 21 billion transistors on a die under 1,000 square millimeters - so the WSE held roughly 50 times more transistors than the largest contemporary GPU and was about 56 times larger in area.