In January, Intel announced its SpeedStep technology, which will bring desktop CPU speeds to laptop users. SpeedStep helps your laptop batteries last longer because the chip steps down its processor speed when you're running on battery power. When you plug into an AC line, you receive the same high CPU performance that only desktop users have enjoyed in the past. Intel created SpeedStep chips in response to market research showing that users run laptops from AC lines about 70 percent of the time.

At first, Intel will implement the SpeedStep technology in the most advanced mobile microprocessors, but this technology will make its way into all Intel mobile chips. The highest performing SpeedStep chip costs $750 and runs at two speeds. When you dock a laptop or plug it into an AC outlet, the chip powers up and runs at 650MHz. When the laptop is mobile and draws from its battery, the chip powers down and runs at the lower, more energy-efficient speed of 500MHz. Laptop users can configure the chip through the Windows Control Panel and make it operate in high-performance mode at any time, even when the chip is running on battery power. This option lets users sacrifice battery life when they need the extra processing speed.

SpeedStep chips offer several performance modes. The top-of-the-line chip draws 1.6 volts in maximum performance mode (650MHz) and 1.35 volts in battery-optimized mode (500MHz). A more economical SpeedStep chip is similar, except that in maximum performance mode it runs at 600MHz. All available SpeedStep chips are Pentium III processors; Intel might make Celeron SpeedStep chips available by late summer.

Intel claims that the chip is compatible with all major PC OSs, including Windows 2000 (Win2K), Windows NT, and Windows 9x, and I see the increased speeds of the current laptops as SpeedStep's main benefit. For years now, laptop CPUs have lagged behind desktop CPUs by as much as 30 percent. Now the top-end speeds of laptops and desktops will be similar.

Although the laptop speed increase is welcome, any road warrior who thinks that SpeedStep chips will make a significant difference on cross-country airplane trips is probably mistaken. First, this new technology provides only about a 30 percent drop in power consumption of the CPU. Second, because the CPU represents less than 25 percent of a laptop's power consumption (screens and disk drives are the two major power consumers), the power savings is about 8 percent at most.