LOS ANGELES--Microsoft on Monday offered the first glimpse of the external HD-DVD drive built for the Xbox 360 game console. Kevin Collins, senior program manager at Microsoft, demonstrated the HD-DVD drive, which he said is scheduled to hit store shelves for the upcoming holiday shopping season, to attendees of the DVD Forum here.

　　The device--about the size of a hardback book--played The Phantom of the Opera as Collins pulled up a menu bar to display a few of its navigation and interactive features that can be called up onscreen while a movie is playing. Collins said Microsoft's HD-DVD drive will be among the least expensive of the HD-DVD players, but he declined to disclose the drive's retail price.

　　"All the audio and video processing is done inside the Xbox," said Collins, who noted that research has shown that a majority of Xbox owners already own high-definition displays. An Xbox drive provides them with all the other equipment they need to watch HD-DVD movies, he said.

　　"This gives consumers choice and keeps their cost down," Collins said Microsoft has chosen to back the HD-DVD format over Blu-ray. Both technologies are vying to replace the DVD format and are represented by consortiums that include electronics makers and Hollywood studios.

　　Game consoles may prove to be a crucial battleground for the two formats, some observers predict. In November, Sony's PlayStation 3 is expected to debut equipped with a Blu-ray drive. In contrast to Microsoft's strategy to go with an external drive, PlayStation's drive will be built in.