道指、标普均创历史新高，芯片股借AI东风飙升，中概股涨跌不一

Market Overview - The U.S. stock market saw all three major indices close higher, with the Dow Jones and S&P 500 reaching all-time highs [1] - The semiconductor sector experienced a strong rally due to a significant shortage of storage chips driven by the AI boom, with Micron Technology leading the performance [1] - The S&P 500's current expected price-to-earnings ratio is approximately 22 times, slightly down from 23 times in November but still above the five-year average of 19 times [1] Sector Performance - The S&P 500's 11 sectors saw the materials sector rise by 2.04%, while energy fell by 2.81% [3] - The semiconductor ETF increased by 2.66%, and the biotechnology ETF rose by 2.33% [3] Company News - xAI successfully raised $20 billion in its E-round financing, exceeding its initial target of $15 billion, with participation from major investors like Fidelity and Qatar Investment Authority [7] - NVIDIA's CFO indicated that the company's revenue forecast has become more optimistic due to strong demand, with data center chip revenue expected to exceed $500 billion by the end of 2026 [8] - Meta announced a pause in its international expansion plans for its Ray-Ban smart glasses due to unexpectedly high demand, prioritizing U.S. market orders [9] - Chevron has booked at least 11 tankers to Venezuela following the U.S. military's control of President Maduro, marking an increase from 9 tankers in December [10]