DELL Inc overtook larger competitor Hewlett-Packard Co in customer satisfaction last year, a sign that Michael Dell's return to the personal-computer maker he founded might be paying off.

Dell lifted its score one point to 75 out of 100 and took second place behind Apple Inc in the University of Michigan's annual ranking of personal-computer makers, Bloomberg News reported. Hewlett-Packard slid three points to 73.

In online services, Google Inc retook the top spot from Yahoo! Inc.

Michael Dell, who returned as chief executive officer last year, unveiled new designs in multiple colors while retooling customer services to regain the PC sales lead lost to Hewlett-Packard two years ago. Competitors suffered more from perceived problems with Microsoft Corp's Windows Vista program.

"Dell is the exception; every other Windows-based PC maker has gone down a significant amount," said Claes Fornell, a marketing professor at the University of Michigan.

The results reflected the investments Round Rock, Texas-based Dell has made in service, including an online tool that let the company fix computer problems remotely, spokesman Bob Kaufman said. In the previous year's study, Dell ranked behind Apple, Hewlett-Packard and the computer industry average.

Dell shares fell 43 US cents to US$24.63 on Monday on the Nasdaq Stock Market. The stock has gained less than half a percent this year. Palo Alto, California-based Hewlett-Packard has lost 12 percent.

The Vista operating system, which went into wide-scale distribution in 2007, probably led to the drop in scores for Hewlett-Packard, its Compaq brand, and Acer Inc's Gateway brand, Fornell said. Customers complained about sluggishness and compatibility problems.

The researchers surveyed 11,000 consumers from March to May. A recent independent survey found 89 percent of Windows Vista users were satisfied or very satisfied with the product, said Mac Brown, a spokesman for Microsoft.

Hewlett-Packard's score would improve following the firm's revamping of customer support and the opening of more call centers, spokeswoman Marlene Somsak said.

Apple had a score of 85, a record high for the computer maker. The score rose because the company made its own software and did not rely on Vista, Fornell said.