Intel and Microsoft are combining their industry power in an attempt to make the HD-DVD format the victor in a battle over a standard to succeed DVD.

Typical DVDs today can hold 4.7GB of information, but two dueling camps are trying to establish a larger-capacity format that will allow for the recording of high-definition television and the backing up of more data. HD-DVD, supported by a Toshiba-led consortium, is up against Blu-ray Disc, which is backed by Sony and others, including the two biggest personal-computer manufacturers, Dell and Hewlett-Packard.

Intel and Microsoft believe weighing in on the HD-DVD side will be enough to tip the balance. "We have a high expectation of having a single format, and that format is HD DVD," said Intel spokesman Bill Kircos.

There are several reasons the two companies went with HD-DVD, said Richard Doherty, Microsoft's program manager for media entertainment convergence. Among them: HD-DVD requires that movies be copied to a consumer's hard drive, making it easier for people to send movies around home networks; the format supports regular DVD recordings on the flip side of the disc, letting people sell hybrid discs to consumers who have DVD players today but fear their discs will be obsolete.

"This announcement does little to shift the momentum that's been building for Blu-ray Disc," said Marty Gordon, vice president of Blu-ray backer Philips Electrics. "It has dramatically more support from the consumer electronics industry, the PC manufacturers and the games hardware manufacturing side, as well as strong support from movie studios, music companies and game software developers."

Blu-ray allies expect to launch their products in the spring, Gordon said, including support for both 25GB and dual-layer 50GB. HD-DVD starts at 15GB, but Toshiba last week announced a 30GB dual-layer disc. Toshiba plans to launch the first HD-DVD drives in Japan this year and worldwide in the first quarter of 2006, Doherty said.

The two camps have held talks to unify their formats, but so far to no avail, and time is running short, with products from both camps scheduled to ship in the next few months.

If the sides don't come together, a host of problems will ensue: Consumers will have to make sure a rented movie or purchased video game is compatible with their drives and players; movie studios, video game manufacturers, and video rental stores will have to stock multiple versions of movies; dual-format drives that bridge the format gap will cost more; and neither standard is likely to catch on as fast as if the industry had coalesced.

It's similar to the classic war over videotape formats, VHS versus Beta, and a smaller skirmish that broke out more recently for rewritable DVDs: DVD-RW versus DVD+RW.

Even at this late stage, it's possible there could be a resolution. "We're very hopeful you could see a unified standard," Gordon said. "It has to be a format that offers the best of both worlds," though, and the Blu-ray camp isn't willing to yield on the capacity issue.

Microsoft also hoped for a resolution, but didn't see one as likely. "We're of the opinion that a unified format would be far preferable. But what was keeping us from the game was our hope for a long time for that to occur," Doherty said.

Gordon said that several of the advantages Microsoft and Intel cite for HD-DVD aren't valid. In particular, he said, 50GB Blu-ray drives are scheduled to ship this spring, with much more capacity than HD-DVD's 30GB. And the managed copy feature that permits movies to be transferred to hard drives isn't "a key differentiating feature" of HD-DVD, because Blu-ray employs the same Advanced Access Content System (AACS) content control technology, he said.

Both sides have support from major computing, consumer electronics, and entertainment companies.

Besides Sony, Dell, and HP, Blu-ray allies include Apple Computer, Electronic Arts, Panasonic, Philips, Samsung, Sharp, Sun Microsystems, Twentieth Century Fox, Vivendi Universal, and Walt Disney.

HD-DVD backers include HBO, NEC, New Line Cinema Paramount Home Entertainment, Sanyo, Toshiba, Universal Studios Home Entertainment, and Warner Home Video.

The divide splits Intel and Microsoft from some of their biggest customers, though. Dell couldn't be reached for comment immediately, but HP isn't changing course.

"HP remains committed to the Blu-ray Disc format because of larger storage capacity, broad industry support and the inherent compatibility that the recording format provides to our customers," the company said in a statement. "HP believes that this announcement from Microsoft and Intel is inconsequential for consumers because they do not deliver products into the marketplace (with a few minor exceptions)."

Blu-Ray has had problems delivering on its promises, though, Doherty said. "The 50GB Blu-ray disc is nowhere in sight. For now, HD-DVD is the capacity leader. And with the hybrid disc, again Blu-ray had a specification, but no actual implementation anywhere in sight."

That issue could cause PC makers to change their minds. "A year and a half ago, they had a really good situation," Doherty said. "Now the playing field has changed."