Data Centers

The bill for the artificial intelligence buildout got more expensive on Wednesday, and investors noticed. Shares of debt-heavy AI infrastructure companies tumbled as the prospect of higher U.S. interest rates revived a basic question about the boom: how much return will all of this borrowed money actually produce?

Microsoft has made its biggest move yet to run its artificial intelligence services on hardware of its own design. On Monday the company unveiled Maia 300, the third generation of its custom AI chip, and said it plans to deploy potentially more than a million of them starting next year in multi-gigawatt installations. Chief Executive Satya Nadella described the rollout as the company's biggest bet yet on its own silicon, and Azure executive Scott Guthrie said Maia is intended to become the primary system for running AI inference across Microsoft's products and services.

Broadcom chief executive Hock Tan thinks the AI boom's new limiting factor is not silicon. Speaking at a panel in Singapore on Monday, Tan said capital — not wafer or memory shortages — will be the biggest constraint on AI development as the industry pushes forward. The company, he said, is working through its wafer and memory shortages. The harder problem, increasingly, is paying for what comes next.

Who pays for the electricity that AI eats? Three senators just published their answer: you do — and Big Tech likes it that way.

On October 9, Senators Elizabeth Warren, Chris Van Hollen, and Richard Blumenthal released a 27-page report, Power and Profits: How the AI Data Center Boom Costs Households and Communities, the product of a nearly yearlong investigation into AI data centers' impact on communities. The inquiry began with information requests sent December 15, 2025, to seven companies: Amazon, Google, Meta, Microsoft, CoreWeave, Digital Realty, and Equinix.

The money funding America's AI buildout is increasingly coming from Europe.

Hyperscalers — the big cloud and AI companies behind the AI boom — have raised $48 billion in European-currency bonds so far this year, according to Apollo's Daily Spark note published this week. That is more than triple what they raised in all of 2025. The tally breaks down to €27 billion in euro-denominated bonds, £13 billion in sterling, and CHF 7.5 billion in Swiss francs.

CoreWeave built its reputation selling raw AI compute. Now it wants to sell the software layer on top of it. At its Fully Connected conference, the company unveiled CoreWeave Forge, a development platform that folds model serving, observability, post-training, and evaluation into a single environment — and it comes with a striking performance claim: a preview feature called RL Rollouts that improved model reload latency by 15x in testing.