On February 27, the U.S. stock market experienced a violent shock.

The Nasdaq Composite Index fell 2.78% in a single day, the largest decline in a month. The S & P 500 Index fell 1.59%. Although the Dow Jones Industrial Average fell slightly (0.45%), the collective decline of the three major stock indexes still left the market shrouded in gloom.The core driving force of this selling wave is undoubtedly the comprehensive collapse of technology stocks-the market value of the semiconductor giant led by Nvidia has evaporated by US$274 billion, and its share price has dropped nearly 20% from its high at the beginning of the year. Its plunge not only dragged down the overall decline of the chip sector, but also triggered deep market doubts about the sustainability of the AI boom.InvalidParameterValue

The trigger for the collapse of technology stocks: Nvidia's "perfect storm"

Nvidia's collapse can be called a "perfect storm" with multiple factors superimposed.Although its latest financial report showed that revenue forecasts still maintained growth, market concerns about a decline in its gross profit margin rapidly grew.The company's quarterly gross profit margin guidance was 75%, which was lower than analysts 'expectations of 76.5%. This slight gap was infinitely amplified in the eyes of investors and became a trigger for selling.The deeper reason lies in the market's reassessment of the AI industry chain.China start-up DeepSeek recently announced the launch of an AI model that costs only 1% of the industry average. This news has been interpreted by some investors as a signal that "computing power demand will fall off a cliff."Although industry leaders such as Microsoft CEO Nadella and Meta's Zuckerberg have said they will not adjust their AI infrastructure investment plans, panic selling by retail investors and hedge funds still caused Nvidia to evaporate nearly US$600 billion in a single day (Extended impact of a historic decline of 17%).InvalidParameterValue

Chain collapse in the semiconductor industry

Nvidia's collapse was quickly transmitted to the entire semiconductor industry chain.The Philadelphia Semiconductor Index fell 6.1% in a single day, Broadcom fell more than 7%, and AMD, Asmail, TSMC, etc. all fell more than 5%.This phenomenon exposed the market's concerns about overheating investment in computing power-Microsoft was revealed to be likely to reduce data center leases, coupled with rumors that the Trump administration plans to impose new restrictions on semiconductor equipment exports, further exacerbating industry uncertainty.It is worth noting that the valuation revision of chip stocks is not an isolated event.Nvidia's share price has soared tenfold in the past two years, and its market value once exceeded US$3.7 trillion, far exceeding Cisco's valuation during the Internet bubble in 2000.The market's controversy over whether valuations overdraw future growth reached a critical point in this plunge.InvalidParameterValue

Double attack of macroeconomic and policy risks

The vulnerability of technology stocks is amplified by macro data.The U.S. Department of Commerce confirmed that the annualized GDP growth rate in the fourth quarter was 2.3%, a significant slowdown from 3.1% in the previous quarter; the number of initial jobless claims climbed to 242,000, higher than the expected 221,000. These two data together point to signs of cooling the economy.At the same time, the Trump administration's tariff policy once again stirred up market nerves.Its threat to Mexico and Canada to restart 25% tariffs, as well as its intention to impose a 10% tariff on China, not only rekindled concerns about a trade war, but also directly hit technology companies that rely on global supply chains.InvalidParameterValue

Sector differentiation highlights the logic of capital hedging

In market panic, the flow of funds shows clear risk-averse characteristics.The financial sector bucked the trend and rose by 0.57%, while the energy sector rose slightly by 0.48%, reflecting investors 'strategic adjustments in the face of rising interest rate expectations. The Federal Reserve may delay interest rate cuts or even restart interest rates, which has widened the net interest margin of bank stocks. Logic has regained popularity.Although defensive sectors such as utilities fell 2.23% due to the broader market, their decline was much smaller than the 3.79% of technology stocks, indicating that some funds began to migrate to stable assets.InvalidParameterValue

The differentiation of Chinese stocks and the global game in the AI industry chain

China stocks failed to survive. The Nasdaq China Golden Dragon Index fell 0.93%, and Jinshan Cloud and Hesai Technology fell more than 10%. However, new energy vehicle companies such as NIO and Xiaopeng Automobile rose against the trend, highlighting structural differences in the industry.It is worth noting that the controversy over the computing power revolution triggered by DeepSeek is essentially a microcosm of the competition for the right to speak in the global AI industry chain.Breakthroughs by China companies in the field of model optimization are shaking Wall Street's traditional perception of "computing power = valuation." This poor perception may lead to the restructuring of the technology stock valuation system.InvalidParameterValue

Market foresight: PCE's ultimate test of data and earnings season

Looking forward to the market outlook, the upcoming January PCE price index will become a key indicator.If core inflation data exceeds expectations, it may strengthen the Fed's hawkish stance and further suppress the valuation of technology stocks.At the same time, as the earnings season comes to an end, the performance of financial giants such as JPMorgan Chase and Goldman Sachs will verify economic resilience, while the profit guidance of technology companies such as Tesla and Amazon may become the new focus of the long-short game.For investors, under the triple pressure of AI bubble correction, policy uncertainty and economic slowdown, it is a rational choice to decentralize allocation, increase the weight of value stocks and defensive assets, or traverse the current volatility cycle.InvalidParameterValue