The first notebooks supporting the next generation of optical media are here, fueling the battle between the two high-definition DVD formats. Sony's $3499 VAIO VGN-AR190G comes with a Blu-ray Disc burner, while Toshiba's $3000 Qosmio G35-AV650 offers an HD DVD drive. Both of these units permit you to watch stunning high-definition movies on their own screens or on a connected HDTV, but we preferred Toshiba's G35-AV650 for its lower price, better ergonomics, and smoother movie-viewing experience.

Large desktop replacement models, the 10.4-pound Toshiba laptop and the 8.3-pound Sony portable both have glossy 17-inch wide-screen displays that are capable of the 1920 by 1200 resolution required for showing high-definition content. The Toshiba's screen, however, uses two lamps instead of one for greater brightness. Both systems feature an HDMI port with HDCP support for connecting to an HDMI-equipped HDTV. If your TV lacks HDMI, though, you're out of luck, since the notebooks' other video outputs--S-Video, composite, and VGA--don't support a high-definition signal. The Sony outputs video at 1080p, while the Toshiba outputs video only at the lesser 1080i, a disappointment considering that Hollywood studios are beginning to encode their discs at 1080p resolution.

As for the optical drives, the Sony model has more features: It's the first mobile optical drive to write to high-capacity Blu-ray write-once and rewritable media (albeit at just 1X). By contrast, the drive in the Toshiba portable is merely an HD DVD-ROM, capable of reading HD DVD movies but not writing to discs. Also, the G35-AV650's ability to play media without booting into Windows does not currently extend to playing HD content, and a future Toshiba firmware update for "instant on" playback of HD DVD movies is as yet undetermined.

The movie-viewing experience was better on the Toshiba than on the Sony. (Not that HD DVD movies are superior, just that the experience of playing movies on the Toshiba was easier.) While we were testing, we didn't have the same movie in both formats, so we had to settle for watching The Last Samurai in HD DVD on the Toshiba and House of Flying Daggers in Blu-ray on the Sony.

Video on the Toshiba model exhibited incredible detail and depth. Playback on the Sony unit was less satisfying: The images had bright, deep color, but whether viewed on the unit's display or on a 1080i plasma TV over the HDMI cable, the video wasn't consistently smooth. We also encountered some finicky resolution issues when we switched between the VGN-AR190G's HDMI input and its built-in laptop screen. Sony attributes these problems to the notebook's nVidia graphics driver and InterVideo DVD playback software, and says it will release a patch.

Both notebooks feature a 2-GHz Core Duo T2500 processor, 1GB of DDR2 SDRAM, and 200GB of storage. The Toshiba produced average gaming performance with its 256MB nVidia GeForce Go 7600 graphics controller, while the Sony did a little better with the GT version of the same chip set. Both laptops produced a solid score of 96 in our WorldBench 5 tests, too. However, the Toshiba was the winner in battery life tests, lasting 3 hours versus the Sony notebook's 2 hours.

Both portables let you plug in coaxial antennas (no HDTV support), and both include built-in TV tuners, Windows XP Media Center Edition, and remote controls. We liked the keyboard and touchpad on the Toshiba better. The Sony notebook's keys were not as well defined, and mouse buttons were poorly designed.

Despite a few limitations, the Qosmio G35-AV650 is a solid, powerful portable that won't disappoint early adopters. Likewise, if you don't mind the heft and need a mobile, high-definition video production system, the VAIO VGN-AR190G should deliver.