U.S. stocks were mixed ahead of Nvidia's earnings Wednesday as a drop in oil prices was offset by concerns about debt incurred to fund the artificial-intelligence boom.

The Dow Jones Industrial Average gained 140.15 points, or 0.26%, to 53417.16. The S&P 500 fell 21.51 points, or 0.28%, to 7652.86 and the tech-heavy Nasdaq Composite lost 200.26 points, or 0.76%, to close at 25980.19.

Oil fell after Treasury Sec. Scott Bessent unveiled new sanctions for about 60 Iran-linked entities, a more modest round of economic warfare than anticipated. Launching "Operation Economic Outcast," Bessent said the administration would eventually impose secondary sanctions on countries doing business with Iran. Oil futures fell $2.05, or 2.4% to $85.01 a barrel.

The yield on the 10-year Treasury note declined 0.034 percentage point to 4.703%. The yield on the policy-sensitive two-year Treasury rose 0.002 percentage point to 4.234%. Elevated Treasury yields have spooked markets in recent weeks. Even a promised intervention from the Treasury Department only briefly reversed the upward trend in long-term yields last week. Federal Reserve Chairman Kevin Warsh could also address Treasury-market volatility in a speech from the central banking conference in Jackson Hole, Wyo., on Friday.

"You have the Treasury [department] with one mission, you have the Fed perhaps with another," said J.D. Joyce, president of Houston financial advisory Joyce Wealth Management. "Eventually, if rates stay too high for too long, that can further hurt the consumer and it can further hurt the overall economy."

The U.S. dollar ticked up against rivals following the latest moves in U.S. trade wars.

Gold futures gained $16.70, or 0.4%, to $4640.80 a troy ounce, and have now risen by 16% from mid-July lows.

Volatility in the semiconductor sub sector continued. Chip makers produce what investors consider the "picks and shovels" of the AI gold rush and have become a bellwether for overall sentiment on the emerging technology. The PHLX "SOX" Semiconductor Sector Index is now down by more than 20% from its record highs in late June, in bear-market territory. Still, the index is up by roughly 60% for the year to date.

Nvidia shares fell 2.9% to $208.48. The U.S. chip maker recently struck a $6 billion deal with software company Poolside and now aims to build one of the world's most powerful open-weight AI models, taking on Chinese competitors such as DeepSeek and Kimi. Open-weight AI models are akin to open-source software, allowing users to see and tweak the source technology as opposed to just seeing the outputs of "black box" models such as OpenAI's ChatGPT and Anthropic's Claude.

Nvidia will report quarterly earnings on Wednesday after the market closes. One strategist said that should restore investor confidence in the AI trade.

The earnings will likely "be another indication that AI is alive and well," said Joyce.

One concern investors have is that tech companies are taking on too much debt to fund AI dreams, just as borrowing costs grow more expensive. Shares of Chinese tech company Alibaba fell overnight after it unveiled a multibillion-dollar AI budget.

Yangtze Memory Technologies, the leading Chinese maker of NAND memory chips, filed for an initial public offering in Shanghai to raise $4.9 billion.

California Attorney General Rob Bonta canceled a planned meeting with Paramount Chief Executive David Ellison where the parties were expected to discuss settling a lawsuit the state led seeking to block the company's $81 billion buyout of Warner Bros. Discovery. Paramount shares were unchanged at $10.35. Warner shares ticked up 0.5% to $28.70.