By Noel Randewich

June 24 (Reuters) – Shares of chipmakers surged late on Wednesday, adding over $400 billion in market ‌value after strong forecasts from Micron Technology and Qualcomm ‌breathed fresh life into Wall Street’s recently waning AI stock rally.

Micron surged ​12% in extended trade after forecasting quarterly earnings above analysts’ estimates, signaling that heavy investments in AI-related infrastructure will drive strong demand for its memory chips.

Also after the bell, Qualcomm ‌said it expects $15 billion ⁠in sales from its data center business by 2029 as it moves beyond its core smartphone ⁠chip business and shifts its focus to AI.

Western Digital, Sandisk and Seagate Technology, which compete with Micron, all jumped more than ​8%.

Arm Holdings ​rallied about 6%, Marvell added ​almost 4% and Broadcom ‌climbed 2%.

Applied Materials and ASML, which sell specialized manufacturing equipment to semiconductor companies, both rose more than 4%.

The blowout forecasts from Micron and Qualcomm follow recent worries on Wall Street that valuations for AI-related companies have become stretched following years ‌of gains. The PHLX chip ​index tumbled 8% on Tuesday, with ​investors also concerned that ​massive spending to build AI data centers may ‌take too long to pay ​off in the ​form of increased revenue and profits.

However, even after this week’s weakness, the PHLX chip index remains up 90% ​so far in 2026. ‌Not including its late-day rally on Wednesday, Micron has ​gained over 260% year to date.

(Reporting by Noel ​Randewich; Editing by Chris Reese)