• All three major indexes closed lower Wednesday.
• Nvidia posted its quarterly results.
• Berkshire Hathaway reached a market cap milestone.

Here are five key things investors need to know to start the trading day:

1. Going down

Stocks saw some pullback on Wednesday, with all three major averages seeing losses. The Nasdaq Composite saw the biggest percentage loss, falling 1.12% to finish the session at 17,556.03. The S&P 500 fell 0.6% to close at 5,592.18, while the Dow Jones Industrial Average moved 0.39% lower to close at 41,091.42. The pullback was pressured by Nvidia's 2.1% drop as Wall Street anxiously awaited the semiconductor's quarterly results after the bell. That led to information technology falling 1.3% in the session. Follow live market updates.

2. Not impressed

Nvidia just beat the Street's earnings expectations. For its fiscal second quarter, the AI darling earned an adjusted 68 cents per share on revenue of $30.04 billion. According to LSEG, analysts expected 64 cents per share on $28.7 billion in revenue. Not only that, Nvidia announced a $50 billion stock buyback and provided a stronger-than-expected forecast. For the current quarter, the chip giant said it expects revenue to come in around $32.5 billion, while analysts were expecting close to $32 billion. However, the stock fell 7% in extended trading on Wednesday. Before the results even came out, Bernstein analyst Stacy Rasgon told CNBC that "buyside whispers" were closer to $33 billion to $34 billion. In other words, for Nvidia to see a jump in shares, it would have had to substantially surpass expectations in its forecast.

3. $1 trillion club

Berkshire Hathaway has officially reached a $1 trillion market capitalization. On Wednesday, Warren Buffett's Berkshire became the first nontechnology company in the U.S. to achieve the milestone after shares moved 0.8% higher to $696,502.02 during the session. That allowed it to hit the $1 trillion mark in market cap, according to FactSet. That "is a testament to the firm's financial strength and franchise value," said CFRA Research's Cathy Seifert. "This is significant at a time when Berkshire represents one of the few remaining conglomerates in existence today."

4. Super delay

Looks like Super Micro Computer is not going to file its annual report on time. The company announced Wednesday that it's "unable" to file the report for the fiscal year with the U.S. Securities and Exchange Commission. "Additional time is needed for SMCI's management to complete its assessment of the design and operating effectiveness of its internal controls over financial reporting as of June 30, 2024," the company said in a release. The shares plummeted more than 23% in Wednesday's session, coming a day after Hindenburg Research disclosed a short position in Super Micro.

5. Stepping down

Salesforce's chief financial officer is leaving her position. The company announced Wednesday that CFO Amy Weaver will step down, though she'll remain in the position until a successor is appointed. Following the change, Weaver will remain at the company as an advisor. According to the company's co-founder, chair and CEO, Marc Benioff, Salesforce will consider internal and external candidates for the role. The announcement came as the company posted better-than-expected second-quarter results and upped its profit forecast for the full year.

— CNBC's Lisa Kailai Han, Hakyung Kim, Kif Leswing, Jonathan Vanian, Ari Levy, Yun Li, Ashley Capoot and Jordan Novet contributed to this report.

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