Chip stocks pulled Nasdaq lower to start the week, as falling oil prices failed to give the markets a broad reprieve.

Nvidia shares were down 5%, pulling its market value below that of Apple's in morning trading. Memory-chip maker CXMT pulled off a blockbuster stock-market debut, soaring more than fivefold to become the most valuable company listed in mainland China. Investors will watch a fresh batch of U.S. tech earnings this week, including for four of the Magnificent Seven, as worries around artificial-intelligence spending resurface.

Global oil prices meanwhile have retreated below $87 a barrel after the Trump administration paused plans to escalate its war in Iran.

The U.S. late last week was preparing for a series of strikes against Iran, but pulled back to allow for diplomacy. The moves rekindled hopes of a peace deal, though pressures on global energy supplies remain in place.

In other market moves, Treasury yields slipped while the Dow industrials edged higher, lifted by a 6% rally in Salesforce shares. The Federal Reserve's interest-rate decision Wednesday, one of the least predictable in years, is also in focus.