Amazon on Thursday began shipping a large-screen, high-definition version of its popular Kindle Fire tablet computers ahead of schedule in a holiday season challenge to Apple iPads.

Kindle Fire HD tablets ordered online were on their way to buyers and more would be available at US consumer electronics shops beginning Friday, according to Amazon.

"Kindle Fire HD has been Amazon's best-selling product worldwide since launch, and that was before we even started shipping the best tablet we've ever built," said Kindle vice president Dave Limp.

"We think customers are going to love web browsing, email, gaming, watching TV shows, reading magazines, and more on the large, stunning HD screen, with fast Wi-Fi and exceptional audio."

Amazon in September unveiled the new Kindle Fire HD priced at $299 in what analysts saw as a clear challenge to the market-leading iPad.

The new Kindle Fire HD has an 8.9-inch (22.6-centimeter) display and was described by Amazon founder and chief executive Jeff Bezos as "the best high-end tablet anywhere, at any price" when combined with Amazon content and services.

The tablet is only 0.3 inches thick, and weighs 20 ounces (567 grams). The Kindle Fire HD has dual-band Wi-Fi and two antennas.

A seven-inch Kindle Fire HD priced at $199 became available in September.

In an even more direct challenge to the iPad, a 4G version of the larger Kindle Fire HD will sell at $499 -- the same price as a basic iPad.

Amazon said that 4G Kindle Fire HD tablets will begin shipping next week.

Offering the Kindle Fire outside the US for the first time, all except the new bigger-screen version went on sale in Europe in October.

Apple early this month released a smaller version of its iPad to take on Amazon and Android tablets having success in that segment of the market.

Profits slide, but Dell says new strategy on track
Dell said Thursday its third-quarter profit slid 47 percent from a year ago, but claimed its new strategy emphasizing software and cloud computing was paying off.

Dell, one of the major PC manufacturers which has been hurt by a shift to tablets and other mobile devices, reported net income fell to $475 million, or 39 cents a share, a penny short of analyst forecasts.

Revenues dipped 11 percent from a year ago to $13.72 billion, also below expectations.

But Dell said its "enterprise solution strategy" showed positive results with server and networking revenue increasing 11 percent.

"In a difficult global IT spending environment we saw solid proof points that demonstrate progress in our strategy," said Brian Gladden, Dell's chief financial officer.

"A highlight has been the strong progress of our newly introduced servers, with our server and networking business up 11 percent. We're also encouraged by early interest in our new Windows 8 touch portfolio and the opportunities it creates for our commercial and consumer businesses."

Texas-based Dell, once the biggest PC maker, has fallen to third place in global sales, according to market tracker IDC.

Dell has expanded its effort in the Internet "cloud" in the face of softening demand for traditional computing hardware and has also moved into software and other services.

Dell announced in June it will use some of its cash stockpile to pay dividends in a bid to boost shareholder value.