On Monday, the second-highest trading volume stock on US markets was NVIDIA (ASX: NVDA), which closed up 2.30% with trading volume of $36.523 billion. NVIDIA announced it will purchase an additional $1.5 billion in shares of SB Energy, a data center developer backed by SoftBank, ahead of the company's US IPO, bringing its total equity investment commitment to $3 billion. SB Energy is advancing data center and associated power infrastructure projects, with its large-scale Ohio data center project set to serve OpenAI. Additionally, several NVIDIA executives disclosed stock transactions to the US SEC, with five executives including CEO Jensen Huang selling a combined nearly 150,000 company shares. Among them, Huang sold approximately 46,000 shares at an average price of about $212 per share. Company filings show most transactions are tied to tax obligations following restricted stock vesting, where the company withholds shares on behalf of executives for tax payment, rather than representing proactive divestment.

The third-highest volume stock was Meta Platforms, Inc. (NASDAQ: META), surging 11.43% with $35.296 billion in trades. Meta's consumer-focused AI agent Muse, launched in early September, is prompting investors to reassess CPU demand driven by agent proliferation. Citing Sensor Tower data, local media reported that Muse has ranked as the top free iPhone app download in the US for three consecutive days since topping the chart last week. Meta states Muse can assist users with tasks such as online shopping, movie ticket purchases, and reservations. An Amazon spokesperson said the Amazon website blocked Muse on Sunday evening. Jefferies analyst Jacky He wrote in a report that as AI agents gain broader consumer adoption, server CPU demand should benefit from higher inference, task orchestration, and infrastructure workloads.

The fifth-highest volume stock was Micron Technology (NASDAQ: MU), closing up 2.77% with $29.27 billion in trades. The Motley Fool analyst Daniel Sparks predicts Micron's profits will surpass Microsoft's by fiscal 2027. This bold call relies almost entirely on memory pricing. Micron's latest guidance indicates net profit in the fourth quarter of fiscal 2026 could reach approximately $35 billion. If that pace continues, its fiscal 2027 profit might exceed Microsoft's. Advanced Micro Devices (NASDAQ: AMD) ranked sixth, jumping 9.95% with $26.885 billion in trades, marking its first-ever close above a $1 trillion market capitalization. Meta's Muse agent, after its launch earlier this month, quickly topped the Apple App Store's free app charts, reigniting investor enthusiasm for CPU makers, as these chips are essential for running agents. Data shows Meta is AMD's second-largest customer, accounting for roughly 5.5% of AMD's revenue. Wedbush analyst Matthew Bryson commented: "AI agents rely heavily on compute-driven applications. The two truly major compute suppliers are Intel and AMD." AMD is viewed as one of NVIDIA's primary competitors in the GPU market and becomes the fourth US chipmaker to surpass $1 trillion in market value, joining NVIDIA, Broadcom, and Micron Technology.

Seventh-place Intel (NASDAQ: INTC) soared 12.14% with $22.998 billion in trades. Reports indicate Intel is extending its advanced packaging strategy into Micro LED substrate technology, with reports of deep collaboration with display panel maker AUO to advance CPO (co-packaged optics) and high-density compute chip integration solutions, signaling the optoelectronic heterogeneous integration path is accelerating toward commercialization. Eighth-place SanDisk (NASDAQ: SNDK) slipped 1.41% with $18.435 billion in volume. Ninth-place Microsoft (NASDAQ: MSFT) rose 1.59% with $13.881 billion in trades. Jefferies issued a research note stating it currently views M365 Cloud as Microsoft's most undervalued monetization lever. While SaaS sentiment remains pressured, dragging software stocks, the firm expects M365 to still benefit from integration and usage-based ARPU growth, potentially marking an inflection point. The firm positions Microsoft as an end-to-end enterprise AI winner, spanning infrastructure to application layers, maintaining a "Buy" rating with a $575 price target. Tenth-place Tesla (NASDAQ: TSLA) gained 3.03% with $13.66 billion in trades. Reports indicate Tesla is advancing a new round of humanoid robot supply chain audits in China's Yangtze River Delta region, with several component suppliers already in its automotive supply chain securing Optimus-related orders. These companies are involved in joint modules, actuators, precision structural parts, and other core electromechanical components for humanoid robots. Industry research analyst Ian Ma believes Tesla's supplier audits are a positive signal for Optimus commercialization, showing the company is preparing for repeatable, scaled production.

Eleventh-place SpaceX (Private) rose with $12.648 billion in volume. SpaceXAI released Grok 4.7 on Monday, calling it the company's most capable model for programming and knowledge work to date. The new model maintains Grok 4.6's base pricing at $2 per million input tokens and $6 per million output tokens, supports a 500,000-token context window, and is integrated into xAI API, Grok Build, and Cursor platforms. The company also launched a faster version, Grok 4.7 Fast, billed at double the standard rate, available exclusively through Cursor and Grok Build. Twelfth-place Apple (NASDAQ: AAPL) advanced 0.85% with $11.809 billion in trades. Thirteenth-place Amazon (NASDAQ: AMZN) gained 1.87% with $11.03 billion in volume. Amazon said it has blocked Meta's new personal AI agent Muse from making purchases on behalf of users on Amazon.com. Meta did not inform Amazon beforehand that Muse would access Amazon.com, and Amazon has not authorized Muse to use its shopping services. Amazon stated Muse does not proactively identify itself as an AI agent when browsing the site, and "appears" to capture and store user credentials while scraping account data, raising security, privacy, and transparency concerns. Fourteenth-place Alphabet Class A (NASDAQ: GOOGL) rose 1.55% with $10.784 billion in trades. Google announced Monday that pre-orders have opened for its high-end Googlebook laptop, which deeply integrates Gemini AI tools for Android users, starting at $899. Initial devices come from Acer, Asus, Dell, HP, and Lenovo, powered by Intel or Qualcomm processors with battery life up to 14 hours. The series combines Android's tech stack with ChromeOS desktop foundations, supporting AI text writing and organization, on-screen question answering, and continuation of tasks from Android phones. Additionally, Google recently acknowledged that its AI model Gemini breached the systems of three real companies during a cybersecurity capability test in May. Sixteenth-place Broadcom (NASDAQ: AVGO) rose 1.60% with $9.516 billion in trades. JPMorgan's latest report projects ASIC/XPU share of AI chip unit shipments will rise to 54% by 2027, surpassing GPUs, and further to 55% by 2028. It estimates the custom AI ASIC market at roughly $60-70 billion in 2026, with compound annual growth exceeding 40-50% over the coming years. Broadcom and Marvell currently hold about 90% market share, with Broadcom at approximately 80-85%, indicating high market concentration. Eighteenth-place Warner Bros. Discovery (NASDAQ: WBD) jumped 10.79% with $7.09 billion in volume. On September 21, Paramount Skydance reached a settlement agreement with California and 11 other US states. Those states had filed lawsuits to block the $110 billion merger between the company and Warner Bros. Discovery; this settlement clears the way for the two Hollywood giants to combine. California Attorney General Rob Bonta announced the settlement at a press conference in Los Angeles that day. Twentieth-place Strategy (NASDAQ: MSTR) surged 9.47% with $6.935 billion in trades. With bitcoin prices continuing to recover, Strategy's bitcoin holdings unrealized profit has expanded to $5.02 billion, reversing from a previous unrealized loss of $10 billion, marking a significant book-value turnaround.