Apple Computer is poised to grab more converts to its Macintosh computers this holiday season, according to a new survey.

The new Mac buyers are driven as much by Apple's decision to switch to Intel processors as they are from the halo effect associated with the company's much-loved iPod portable music players.

In its latest survey, ChangeWave Research found a large and growing pool of consumers who say they're more likely to buy one of the new Intel-based Macs.

The survey of 3,046 members of the ChangeWave Alliance shows that 37% say they're more likely to buy an Apple computer because of the Intel chips. That's nearly double the 19% found in a June 2005 survey, taken just after Apple said it was switching to Intel chips for its Mac computers. It had used chips made by IBM and Freescale Semiconductor.

Members of the ChangeWave panel tend to be more tech savvy than average consumers. The group is made up of 9,000 business, technology and medical professionals who are working on the front line of technological change.

"In a world where a 1% market share change represents $2 billion in sales, we're forecasting a historic market share shift in the PC space for laptops and desktops with these new Intel-based Macs," said Tobin Smith, founder of ChangeWave Research and editor of ChangeWave Investing. "Market share grabs like this just don't happen in the PC world. Our numbers say that the Mac is surging."

Apple's share of laptops bought July-September was up 3 percentage points to an all-time high of 12% among alliance members. Its share of desktops purchased the past 90 days fell 4 points to 7%. In the next six months, Apple's share of all planned desktop purchases is up 4 points to 18%. Its share of planned laptop purchases is down 2 points to 17%.

ChangeWave has found a clear pattern of increased likelihood to buy iMacs, along with increased actual purchases by consumers, since the Intel announcement, Smith says.

Apple's U.S. market share was 4.8% in the second quarter, up from 4.4% a year earlier, research firm IDC says. Apple's share of the U.S. notebook computer market was 7.7%, up from 6.3%. Apple's worldwide market share was unchanged at 2.5%, IDC says.

IDC analyst David Daoud says the Intel processors have improved the speed and performance of Macintosh computers.

But the third and fourth quarters are most competitive for PCs. The back-to-school and holiday shopping seasons are much more about low-priced machines. That's where Dell, Hewlett-Packard and Gateway compete, Daoud says.

Apple is strongest in the second quarter, when schools do much of their PC buying, he says.

Apple is set to report fiscal fourth-quarter results on Wednesday. Analysts polled by Thomson First Call expect the company to earn 51 cents a share, up 34% from a year ago. Wall Street is looking for sales to rise 27% to $4.66 billion.

Apple could benefit from the delay of Microsoft's Windows Vista operating system, now due in January instead of November.

The ChangeWave survey also found that HP's share of desktop purchases over the past 90 days rose 6 points to 26%. HP's share of laptop purchases fell 1 point to 20%.

Planned purchases of HP PCs over the next 90 days appear mixed, with laptops at 23%, up 5 percentage points, and desktops at 22%, down 4 percentage points.

Dell's share of laptops purchased fell 3 percentage points to 33%. Its share of desktops was unchanged at 41%. Dell's share of planned desktop purchases plunged 6 percentage points to 40%, its lowest level in over a year.