03:51 PM EDT, 07/27/2026 (MT Newswires) -- (Updates with index/price moves and company/geopolitical news from the first paragraph.)

US equity indexes traded mixed as investor concerns grew over circular investments in the artificial intelligence industry and as a pause in strikes on Iran entered its third day.

The Dow Jones Industrial Average climbed 0.5% to 52,193.5, and the S&P 500 rose 0.1% to 7,419.7 ahead of Monday's close. The Nasdaq Composite slipped less than 0.1% to 24,964.2. Technology was the third-worst performer.

Nvidia ( NVDA ) has agreed to expand its partnership with South Korean conglomerate SK Group through an artificial intelligence infrastructure initiative valued at more than $500 billion. The deal announced Saturday includes a long-term partnership between Nvidia ( NVDA ) and SK Hynix ( SKHY ) that will provide the US technology giant a stable supply of next-generation AI memory. Nvidia's ( NVDA ) shares dropped 4.4%, the Dow's steepest decliner. The SK Hynix ( SKHY ) stock plummeted 5.6%.

Separately, Nvidia ( NVDA ) is in talks to provide a roughly $250 billion financial backstop for Microsoft ( MSFT )-backed (MSFT) OpenAI as part of a massive data center project in southern Ohio that could cost more than $500 billion, The Wall Street Journal reported Sunday.

VanEck Semiconductor ETF ( SMH ) , with net assets of $77.2 billion, fell 2.1%.

In geopolitical news, the US paused military attacks against Iran over the weekend, while Tehran also refrained from retaliatory action, according to a Commerzbank note. "They asked us very nicely, 'Please stop, let's meet,'" Trump told reporters aboard Air Force One, according to CNN. "And that's where we are right now, see what happens. If we don't make a deal, we go back to the same thing."

Iran's Foreign Ministry said there are no current negotiations with the US, CNN reported.

Almost all of the 78 vessels that crossed the Strait of Hormuz since Saturday used the route designated by Iran, and none were recorded using the southern route near Oman's coast promoted by the US, CNN cited Marisks, a shipping intelligence group.

The front-month US West Texas Intermediate sank 7.8% to $82.39 a barrel, and global benchmark North Sea Brent plunged 8.9% to $88.19 a barrel.