Ultrabooks hit the shelves: Acer Aspire S3 vs. Asus Zenbook UX31

Being thin never seems to go out of style, and the latest notebooks take this ideal to a new extreme. Called ultrabooks, these devices are thinner, sleeker and lighter than the typical laptop, yet they offer a long battery life and a full set of features.

Intel has been hyping ultrabooks throughout the fall, apparently hoping that the new devices will take the notebook market by storm. The company even set up a $300 million fund to help manufacturers develop components for the new class of ultrathin, lightweight laptops. Intel's executive vice president Sean Maloney told attendees at this summer's Computex show in Taipei that the goal is to have ultrabooks account for 40% of consumer notebook sales by the end of 2012.

Independent observers aren't so sure. "The ultrabooks will be popular, but that's very optimistic," explains Bob O'Donnell, vice president for clients and displays at IDC. He forecasts that the ultrabook market could grow from a niche this year to 12% of the consumer notebook market by the end of next year. "By 2015, ultrabooks should account for 25%, at best," he adds.

To see if this new notebook category lives up to its hype, I got my hands on the first two ultrabook PCs on the market: Acer's Aspire S3 and Asus' Zenbook UX31. These are appearing quickly; by the end of 2011, there could be as many as a dozen ultrabook models from the usual suspects: Dell, HP, Lenovo, Samsung, Toshiba and others.

What exactly is an ultrabook? According to Intel, to qualify as an ultrabook, systems should meet five basic requirements (PDF):

• Be less than 21 millimeters (about 0.8 in.) thick.
• Wake quickly from sleep mode.
• Have a battery life of five hours or more.
• Be able to tap into the system's BIOS to use Intel's chip-based Anti-Theft and Identity Protection Technology, which are intended to keep personal information safe and remotely disable the machine if it's lost or stolen.
• Be powered by low-voltage Intel Core processors. The current crop of ultrabooks uses the Sandy Bridge chips; in 2012, the ultrabooks should be based on the third-generation Ivy Bridge processors, which will offer lower power use and enhanced graphics.

Give and get

Compared to a typical general-purpose laptop -- say, a Lenovo IdeaPad Z370 -- an ultrabook is roughly 50% thinner and lighter, yet has similar processing power and the same display size. But what do you have to give up?

Like other thin notebooks such as the MacBook Air, ultrabooks lack a DVD drive. Plus, the first generation of ultrabooks will have the bare-minimum selection of ports; some will require adapters for connecting to anything other than a USB device.

The biggest thing you'll have to give up to join the ultrabook crowd, though, is the ability to remove the system's battery and put in a fully charged one. That's because ultrabooks are expected to have sealed cases with non-removable batteries that can only be changed by the vendor.

This could be important to travelers because, in my testing, neither of the two ultrabooks I looked at met the five-hour minimum battery life. Granted, that testing, which involves playing a series of six HD videos over and over again until the battery runs out of power, is harsher and more pessimistic than the BAPCO MobileMark 2007 application usually used by vendors to verify battery life. But neither the Aspire S3 nor the Zenbook UX31 came close to five hours of battery life.

Once the Ivy Bridge processors ship in 2012 -- no official date has been announced -- they should offer at least an hour more of battery life over notebooks that use older processors. These new ultrabooks are obviously meant to compete directly with Apple's popular MacBook Air. When Ivy Bridge hits the market, we may really have a horse race.