Hewlett-Packard is offering customers who buy an HP desktop or laptop an upgrade to Windows 7 at no charge, once the operating system becomes available in the fall.

The offer comes under Microsoft's Windows 7 Upgrade Option, a program that officially begins June 26. However, HP said it would offer the upgrade option with computers bought June 25 or after.

HP certainly won't be the only major computer maker joining Microsoft's upgrade program. Without it, many potential PC buyers would likely wait until systems ship with the new OS, which is considered a better OS than the current Vista. Microsoft is scheduled to release Windows 7 Oct. 22.

However, HP is not offering the free upgrade with all its systems. The company is advising PC shoppers to go to its Web site to check on system eligibility. Customers who qualify will receive the Windows 7 upgrade and an upgrade utility disk with a step-by-step guide for installation, starting after the release of the OS.

HP claims its utility disk will identify and install most necessary drivers during the upgrade process. The company also plans to continually upgrade its support site with drivers for graphic cards and attached peripheral hardware, as they become available.

For customers who have already purchased PCs with Vista, HP said the systems meet the hardware requirements to run Windows 7. Those upgrades, however, will not be free.

Microsoft on Thursday released pricing for Windows 7. Upgrading to the Home Premium and Professional editions will cost $119 and $199, respectively.

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