SpeedStep Keeps Mobile Users Juiced

These Batteries Endure a Cross-Country Flight

The Dell Inspiron 7500, carrying a 12-cell lithium ion battery, wins bragging rights as the endurance champ: It lasted a whopping five hours and six minutes at 500 MHz. When we stepped the Dell up to 650 MHz, its battery held out an even five hours. The HP OmniBook 4150, with a nine-cell lithium ion battery, lasted 3:51 at 650 MHz and 3:48 at 500 MHz. The IBM ThinkPad 600X, which has a six-cell lithium ion battery, lasted 2:40 at 650 MHz and 2:26 at 500 MHz.

Of course, some tasks push your notebook's CPU harder. If your work involves constant number-crunching or multimedia creation, or if you want to watch DVD movies on a cross-country flight, take note. In our informal testing of the notebooks running a DVD movie, we found battery life improved as much as 14 percent when the processor stepped down to 500 MHz--a gain of 21 minutes for the Dell unit, for example.

On the speed front, our PIII-650s trounced the previous mobile champs, running about 16 percent faster than PIII-500 notebooks on the PC WorldBench 98 test suite. At 650 MHz, the three units finished in a virtual tie: The IBM ThinkPad scored 269; the HP, 266; and the Dell, 264. At their 500-MHz speed settings, the machines' scores resembled those of existing PIII-500 notebooks, across a range from 237 for the IBM to 233 for the Dell.

Guts and Bolts

So which of these three notebooks is right for you?

A true desktop replacement, the $4238 Dell Inspiron boasts a brilliant 15-inch thin-film transistor screen with 1400-by-1050 resolution and a roomy 25GB hard drive. Two media bays can accommodate various modules, including a combination DVD-ROM/LS-120 drive. These modules are not hot swappable. Unfortunately, this unit is more than two inches thick and weighs 10.5 pounds with the DVD-ROM/floppy combo drive and AC adapter. You'll need a big briefcase.

The $4199 HP OmniBook 4150 weighs considerably less--only 7.6 pounds with the DVD-ROM drive and AC adapter--but has robust features. It includes an 18.1GB hard disk, a crisp 14.1-inch TFT screen, a touchpad, and a pointing stick. You can hot-swap an array of modules in the single media bay.

If you want to shed every quarter-ounce possible and can live with shorter battery life, consider the $4408 IBM ThinkPad 600X. It weighs in at 7 pounds with DVD-ROM and external floppy drives, with AC adapter attached. (You can lighten your load by traveling without the drives.) At 13.3 inches, its screen is smaller than the others, however, and it has a relatively small 12GB hard disk. Like the HP, the ThinkPad 600X has one media bay to handle various modules, but IBM doesn't offer hot-swap capability.

Do I Hear 750?

The race continues. Expect PIII SpeedStep chips to exceed the 750 MHz speed limit by year's end. Mobile Celeron processors will also get faster, reaching 600 MHz or more--but they won't get SpeedStep, Intel says. Advanced Micro Devices plans to release its answer to SpeedStep, code-named Gemini, at midyear in mobile K6-2+ chips starting at about 500 MHz. AMD will also use Gemini technology in mobile Athlon chips, expected in the second half of the year.