SITUATION EXPLAINED: a16z raised a $1.1 billion fund for AI hardware. • The Machine Age Fund, from Ben Horowitz, Martin Casado, Raghu Raghuram, David Ulevitch, and David George • It covers chips, memory, networking, storage, and full systems from data centers to robotics to home AI appliances • Every layer is hitting the wall of today's supply chain capability and the limits of physics • Compute density per rack is up 28x from H100 to Rubin, and rack power goes from 5-10 kilowatts to a full…