From the start, notebook vendors have raced to speed up their notebooks but almost always at the expense of battery life: faster processors meant limited time away from an outlet. Thankfully, times change. Rather than throwing more megahertz at computing tasks, Intel's new Pentium M processor, which makes its long-awaited debut today, significantly increases notebook battery life. One notebook we tested--IBM's ThinkPad T40--hit the seven-hour mark.

Sound like a dream come true? Consider that the Pentium M is like no other processor. Based on a 0.13-micron design, the chip has an astounding 77 million transistors, many of which are taken up by the chip's megabyte of cache for the most-used instructions and data. This chip's real boost comes from its ability to predict what the next task will be and start on it or shut itself down between clock cycles to save power. As a result, it not only handles tasks more efficiently, it also uses less power.

Centrino and the name game
Intel has created a confusing name game with the Pentium M notebooks. You've probably heard the buzz about Centrino--Intel's processor-chipset-wireless triad. But only those systems that use Intel's new processor, the 855 chipset, and a Wireless Pro (802.11b) solution can use the Centrino name and logo. The rest have to settle for plain ol' Pentium M.

We put seven of the first Pentium M notebooks to the test at CNET Labs. Three were preconfigured as true-blue Centrinos: the Toshiba Tecra M1, the Acer TravelMate 803LCi, and the Gateway 450. Three of the others leave you the option of making your notebook a Centrino when you buy, depending on which wireless solution you choose. And one notebook, the Compaq Evo N620c, uses only a Phillips Agere wireless adapter, so it's not a Centrino at all (even though it has a Pentium M and the 855 chipset). But don't get hung up on the fancy new name. Our experience--and that of the vendors--is that the wireless radios are roughly equal, with the software being the biggest differentiator among them. In other words, a Centrino by any other name may run just as sweetly.

Look for Intel to up the ante in a few months with a new wireless 802.11a/b adapter design, code-named Calexico. (At present, the upcoming adapter is a/b only. The 802.11g spec hasn't been ratified by the IEEE.)

Much improved battery life
The magnificent seven notebooks that we looked at increased overall performance by an average of about 20 percent, compared to the older Pentium 4 and Pentium 4-M notebooks. Battery-life improvements, meanwhile, were much more impressive. The seven notebooks achieved battery-life scores from three and a half hours to an astounding seven hours. As a result, not only will Pentium M notebooks run longer, but the new Intel solution will lead to a renaissance in laptop design, from thin-and-light systems that weigh much less than ever to desktop replacements that don't need a second battery.

Intel's progress may sound like a win-win situation for notebook users, but every step forward involves a step back. These systems will cost about $300 more than their predecessors, making older systems a better--albeit heavier--value. Nevertheless, whether you call them Centrino or Pentium M, these high-performance notebooks were born to run.

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