Microsoft chairman Bill Gates said his company might ship a new version of its Windows operating system as soon as 2009.

The news agency Reuters quoted Gates on Friday as saying that Windows 7 may be released "sometime in the next year or so." That would put the software ahead of the three-year cycle that Microsoft normally works on for OS releases.

The current version of Windows, known as Vista, shipped in January 2007.

Microsoft to date has said little about Windows 7, which has been in development under the code name Blackcomb. It was generally believed that the OS would ship in the 2010 timeframe. In response to an inquiry from InformationWeek, Microsoft said in a statement that Windows 7 is "scoped to three years from Windows Vista Consumer GA. As is standard with the release of a new product, we will be releasing early builds of Windows 7 prior to its General Availability as a means to gain tester feedback."

If Microsoft is moving up the release date for Windows 7, it may be because Vista has received only a lukewarm embrace from home and business computer users. Many have complained about Vista's hefty resource requirements and lack of compatibility with their existing applications.

To experience all of Vista's features, PC users need a computer with at least a 1-GHz processor, 1 GB of memory, and a 40-GB hard drive. By contrast, Windows XP Professional requires only a 300-MHz processor, 128 Mbytes of RAM, and a 1.5-GB disk.

Dissatisfaction with Vista has led Microsoft to extend the life of the older Windows XP OS for longer than originally planned.

Microsoft said Thursday that it would allow computer makers to continue to sell Windows XP on "ultra-low-cost PCs" for an extended period.

Microsoft said it would allow system vendors to preload the Home edition of Windows XP on ULCPCs through June 2010, or one year after the next version of Windows becomes generally available.

Microsoft defines ULCPCs as, among other things, systems that use discount-line processors and lack a separate graphics card. Such low-spec machines would be incapable of running Vista.

Gates was speaking at a seminar on corporate philanthropy in Miami, Reuters said.