Sandisk, Micron Top S&P 500 as AI Rally Meets Valuation Scrutiny

On July 6, 2026, market commentary focuses on Sandisk, Micron, and Intel as the S&P 500's standout first-half performers, with gains of 858%, 300%, and 278% respectively through June 30. Driven by AI-fueled memory-chip shortages, the rally propelled the index to a 9% year-to-date advance and 95% rise since 2023. While Micron's outlook for tight supply extending beyond 2027 supports further momentum, stretched valuations—Intel trading at 90-137x forward earnings despite a $4.3 billion Q1 loss—now raise doubts about sustainability. Earlier July 5 analysis highlighted the S&P 500's strongest quarter since 2020 but warned of narrow leadership and potential rotation. Analysts favor Micron over peers on valuation and supply dynamics.