On July 1, chip stocks recorded their best quarterly performance in history, continuing a strong upward trend this year driven by robust demand for artificial intelligence devices. However, following recent stock price fluctuations, investors are beginning to question how long this rally can last. CJ Muse, Senior Managing Director and Technology Industry Analyst at Cantor Fitzgerald, stated, "The main theme over the past six months has been the market's comprehensive bet on AI infrastructure, but now people are starting to ask whether this is sustainable and whether we should be concerned." The Philadelphia Semiconductor Index rose 3.9% on Tuesday, with a second-quarter increase of 88%, marking its best quarterly performance ever. The index has risen 101% in the first half of the year, on track for its best annual performance in history. In contrast, the tech-heavy Nasdaq 100 index rose 28% in the second quarter, and the S&P 500 index increased by 15%, both achieving their best quarterly performance since 2020, but still significantly lagging behind chip stocks. However, just as the market began to celebrate, last week's sell-off sounded alarm bells for investors. As Wall Street increasingly questions whether chip demand can be sustained, the Philadelphia Semiconductor Index fell 7.9% last week, recording its largest weekly decline since April 2025. On Monday, the index briefly dropped 3.2% during trading but ultimately closed up 3.8%, indicating heightened volatility.