Nvidia has also struck deals to buy or effectively buy smaller competitors. Late last year, it said it would spend roughly $20 billion to license the technology of the chip start-up Groq and hire its top executive. In September, the company said it would buy Hugging Face, a library of open artificial intelligence models, for $12.9 billion.

Deals like that are the lifeblood of the financial world, producing fees for bankers and lawyers who charge thousands of dollars per hour. And Nvidia was increasingly reloading to do even more; this summer, with the help of three big banks, it completed its first bond offering in five years.

In turn, Wall Street firms were so enthusiastic to ingratiate themselves with Mr. Huang and Nvidia because he could mobilize other firms to spend hundreds of billions of dollars too, or at least promise to.

In one illustrative deal, Mr. Huang rang up David M. Solomon, Goldman Sachs’ chief executive, and others, with the idea that the bank and rivals assemble a joint consortium to lend to companies in need of expensive chips. Not a dime had been raised and even some inside the companies were unaware of it when Mr. Huang nonetheless corralled the firms’ top brass in August to appear on CNBC and announce a half-trillion dollar target. Wall Street’s titans said they would do practically anything to help Mr. Huang keep the money rolling into A.I.