(Yicai) July 27 -- Chengxin Memory Technology has become China’s most valuable listed company after the memory chipmaker’s shares skyrocketed on their first trading day in Shanghai.

CXMT [SHA: 688825] closed up 466 percent at CNY49 (USD7.24) per share on Shanghai’s Nasdaq-style Star Market today, after earlier surging by as much as 539 percent from its initial public offering price of CNY8.66 (USD1.27).

With a market capitalization of CNY3.28 trillion (USD484.2 billion), CXMT blew past fellow chipmaker Semiconductor Manufacturing International Corporation [SHA: 688981] at CNY1.23 trillion and Industrial and Commercial Bank of China [SHA: 601398] at about CNY2.76 trillion.

CXMT kicked off the process for its Star Market listing on July 9, with pricing finalized on July 14. The offering raised CNY66.6 billion after the 15 percent greenshoe option was exercised. The firm intends to use the proceeds to expand memory production capacity, advance dynamic random-access memory technology, and support future-looking DRAM research programs.

CXMT’s share of the global DRAM market has grown rapidly, increasing to 8 percent in the first quarter of this year from 3 percent a year earlier, according to data from research firm Counterpoint. South Korean rivals Samsung and SK Hynix had 38 percent and 29 percent, respectively, while US competitor Micron Technology had 22 percent.

But CXMT’s stellar debut failed to boost other Chinese mainland-listed memory chip stocks, as CXMT is the only listed company making DRAM wafers.

GigaDevice [SHA: 603986] sank 5 percent to sloce at CNY434.03 (USD64.13), Biwin Storage Technology [SHA: 688525] fell 2 percent to CNY241.13, Longsys Electronics [SHE: 301308] edged up 1.1 percent to CNY373.90, after earlier plunging by as much as 5.7 percent, and Puya Semiconductor [SHA: 688766] declined 4.6 percent to CNY371.78.

Many of these stocks saw big price gains during the first half. Since late last month, the sector has undergone a pronounced correction. For example, flash and DRAM supplier Longsys soared 189 percent in the first half, but it has retreated 47 percent since then. A similar boom-and-correction cycle has occurred across much of the memory sector.

Disappointing earnings guidance from several companies has weighed on the sector, prompting investors to question whether the broad first-half rally can be sustained.

Demingli Technology, another major storage module supplier, said it expects a first-half net profit of CNY5.7 billion to CNY6.5 billion (USD842.2 million to USD960.5 million). Based on its first-quarter figures, profit likely fell 5.7 percent to 30 percent in the second quarter. Demingli’s shares [SHE: 001309] have lost about 59 percent of their value since reaching a record high on June 26.

Editors: Tang Shihua, Futura Costaglione