Updated from 7:17 a.m. EDT If there's a demand slowdown afflicting the technology sector, it isn't being felt at Dell Computer ( DELL). The personal-computer giant Friday raised its estimate of second-quarter earnings, saying it now expects to turn a profit of 31 cents a share in the three months to July 30, up from previous guidance of 29 cents a share. The company still expects to post revenue of $11.7 billion. Analysts surveyed by Thomson First Call were expecting the company to earn 29 cents a share on revenue of $11.7 billion. In premarket Instinet trading, the stock was up 43 cents, or 1.2%, to $35.30. Also, in a transition that the company first outlined in March , Kevin Rollins formally became chief executive, relinquishing his role as president and chief operating officer. Founder and former head Michael Dell will stay on as chairman of the board and has said he'll remain deeply involved in day-to-day business. Dell plans to focus on trends in technology and customer preference, including research and development, while Rollins will be in charge of corporate strategy and operations. Dell shares were recently up 59 cents or 1.7% to $35.46. The new estimate followed generally upbeat second-quarter earnings from IBM ( IBM) Thursday, and could help support the recently beaten-down Nasdaq in Friday trading. Dell said the 2-cent-a-share improvement in guidance reflects roughly 1 extra cent of operating profitability with the rest coming from a lower tax rate. The company said "profitable growth remains broadly based. Highlights in the current quarter include robust sales of enterprise systems and services, gains in markets outside the United States, and shipments to U.S. small- and medium-business customers." Dell cited third-party estimates showing its overall global market share in the second quarter rose to more than 18%, up a percentage point from the same period a year ago. "In Europe, the Middle East and Africa, Dell narrowed the quarterly gap between itself and the region's largest player to just 5.4 share points, down from 8 points a year ago," it said.