Shares in China's biggest memory chip maker, ChangXin Memory Technologies (CXMT), surged more than 470% on its debut on the Shanghai Stock Exchange's Star Market, pushing its valuation to roughly 3.3 trillion yuan ($487.3bn; £364.9bn). That makes it the most valuable listed company in mainland China - quite the flex, especially given the global tech stock selloff this month.

CXMT makes dynamic random-access memory (Dram) chips, the kind that power AI data centres, phones, PCs, and tablets. Founded in 2016 by Chairman Zhu Yiming and based in Hefei, Anhui Province, the company plans to use IPO proceeds to boost production and R&D. The stellar performance offers some comfort to Chinese officials, who've been scrambling to curb a stock market slump that wiped out over $1.5tn recently.

Analysts attribute the jump to demand far outstripping supply - only 7% of shares are available for trading, as Anna Macdonald of Hargreaves Lansdown noted. It also underscores Chinese investors' hunger for homegrown chipmakers as Beijing pushes for tech self-reliance. Currently, Samsung Electronics, SK Hynix, and Micron dominate the Dram market with about 90% of global production.

Meanwhile, SK Hynix raised $26.5bn in its New York share offering earlier this month, the largest ever listing by a foreign firm in the US. Its shares surged 17% on Nasdaq debut before settling down. SK Hynix's market value topped $1tn in May, riding the AI chip boom.