(Adds estimates, share movement)
Jan 25 (Reuters) - Western Digital Corp reported a slightly better-than-expected 9.2 percent jump in quarterly revenue on Thursday, as it benefited from healthy pricing for NAND memory chips and strong demand for memory chips used in PCs and smartphones.
The company's revenue rose to $5.34 billion in its second quarter ended Dec. 29 from $4.89 billion a year earlier.
Analysts on average had expected revenue of $5.30 billion, according to Thomson Reuters I/B/E/S.
Western Digital posted a net loss of $823 million, compared with a profit of $235 million last year, due to a $1.6 billion charge related to new U.S. tax laws.
Excluding items, the company earned $3.95 per share, above expectations of $3.79 per share.
Shares of the data-storage device maker, which closed up 1.2 percent in regular trading on Thursday, were down 3.7 percent at $84.70 after the bell.
After a blistering year-and-a-half long surge, a sudden drop in some memory prices, followed by Samsung Electronics Co's disappointing profit estimate earlier this month, is causing jitters among investors who had bet the chip boom would last at least another year.
Western Digital is expected to give its March-quarter financial forecast on an analyst call later in the evening.
Concerns over Western Digital's ability to access crucial NAND chips supply were eased in December when the U.S. chipmaker and its joint venture partner Toshiba Corp settled a long-running dispute over the Japanese company's plans to sell its chip unit.
As part of the settlement, Toshiba and Western Digital will extend existing agreements for their chip joint ventures in Yokkaichi, central Japan, until 2027 or later. (Reporting by Munsif Vengattil and Sonam Rai in Bengaluru; Editing by Savio D'Souza)