Major U.S. equities indexes were mixed in the midweek session as the truce between Iran and Israel appeared to hold steady, with President Donald Trump indicating that the U.S. would hold meetings with Iran next week.

Investors were also monitoring the second day of testimony in Congress from Federal Reserve Chair Jerome Powell, who emphasized the need for the central bank to account for the possibility of persistent inflation related to U.S. tariff policies.

The S&P 500 was essentially flat on Wednesday, ending a fraction of a point below the previous session’s closing level and remaining just below its all-time high. The Dow slipped 0.3%, while the Nasdaq closed 0.3% higher.

Shares of artificial intelligence semiconductor behemoth Nvidia (NVDA) jumped 4.3%, lifting the stock to its highest-ever close and returning the company to the top spot in the list of the world’s most valuable companies by market capitalization. Wednesday’s gains came as Bank of America analysts highlighted Nvidia’s leadership in the AI market, while Loop Capital analysts raised their price target on Nvidia stock, forecasting an oncoming “golden wave” in the adoption of generative AI technology.

Paychex (PAYX) shares dropped 9.4%, losing the most of any S&P 500 stock, after the payroll and human resources services provider reported lower-than-expected sales for its fiscal fourth quarter. Although revenue was up 10% from the year-ago period, the majority of those gains stemmed from the acquisition of human capital management, or HCM, software firm Paycor, which closed in April. Paychex also provided full-year sales and profit guidance that came in below consensus estimates. Shares of fellow HCM software providers Paycom (PAYC), Dayforce (DAY) and Automatic Data Processing (ADP) were all down more than 4%.

Cereal maker General Mills (GIS) missed fiscal fourth-quarter sales estimates and projected a larger-than-anticipated profit decline in fiscal 2026, and its shares fell 5.1%. A decline in the company’s North America Retail segment weighed on its results. The parent company of Cheerios and Bisquick baking mix anticipates that the uncertain macroeconomic environment will continue to affect consumers. CEO Jeff Harmening said General Mills intends to focus on reinvigorating volume-driven organic sales growth.

Tesla (TSLA) stock slipped 3.8% after the the European Automobile Manufacturers’ Association reported that the automaker’s new car registrations in the European Union were down more than 40% year-over-year in May. This marked a fifth straight month of declines for Tesla in the region, even as overall battery electric vehicle registrations have consistently moved higher.

Super Micro Computer (SMCI) shares soared 8.8%, logging the top daily performance in the S&P 500. With Wednesday’s gains, the stock clawed back the steep losses posted earlier in the week after the server maker announced a plan to issue $2 billion in convertible notes. Although news of the offering raised concerns about potential share dilution, Supermicro said it would dedicate part of the proceeds to capped call transactions designed to mitigate the dilutive impact.

Northern Trust (NTRS) stock advanced 4.8%, extending gains posted earlier this week following news that Bank of New York Mellon (BK) had approached the smaller wealth and asset management firm about a potential merger. Additional reports Wednesday indicated that talks between the two companies have been occurring for months, suggesting that negotiations may be further along than previously believed, although Northern Trust has said that it is committed to remaining independent.