Intel Corp., the world’s largest computer-chip maker, said second-quarter earnings rose 44% on its first sales increase in six periods. The stock dropped after the company’s profit margin trailed forecasts.

Net income increased to $1.28 billion, or 22 cents a share, from $885 million, or 15 cents, a year earlier, the Santa Clara, Calif.-based company said yesterday in a statement. Revenue advanced 8.4% to $8.68 billion.

Demand for memory chips used in mobile phones missed Intel’s estimates, dragging down profit margins, the company said. The chief executive officer, Paul Otellini, is shedding the business to focus on more lucrative microprocessors for computers and winning back orders from rival Advanced Micro Devices Inc.

“I would have liked a little more upside given all the positive data points we had for PC momentum,” a fund manager at Thrivent Financial for Lutherans in Appleton, Wis., which oversees $65 billion including Intel shares, James Grossman, said.

Intel’s stock dropped 4.7% to $25.10 in extended trading after the report. The shares had risen 38 cents to $26.33 at 4 p.m. New York time in Nasdaq Stock Market trading and have gained 30% this year, making them the fourth-best performer on the Dow Jones Industrial Average.

Intel’s gross margin, the percentage of sales left after production costs, totaled 46.9% in the period, missing the midpoint of the company’s forecast range.

Net income included a tax benefit of 3 cents a share, Intel said. Sales beat analysts’ estimates of $8.54 billion, the average projection in a Bloomberg survey. In April the company had predicted second-quarter sales would be between $8.2 billion and $8.8 billion.

Intel, whose results are viewed as an indicator of demand for computers and related components, kicked off quarterly earnings announcements for the technology industry along with Yahoo! Inc. Intel’s microprocessors run more than 70% of the world’s personal computers. The company forecast sales of $9 billion to $9.6 billion for the current quarter, compared with an average estimate of $9.3 billion.

Mr. Otellini shed money-losing businesses, cut more than 10,000 jobs and accelerated product introductions to revive results after a slump last year. PC demand is climbing, helped by orders in countries such as China.

Intel gained 6 percentage points of market share from Advanced Micro in the first quarter after ending 2006 with its share at an 11-year low. Advanced Micro won orders by being the first to come out with new technology.

Since then, Sunnyvale, Calif.-based Advanced Micro was late introducing Barcelona, its latest server chip, and the processor is slower than expected, JPMorgan Chase & Co. analyst Christopher Danely in San Francisco said.