The iPhone 3G isn't the only thing being released this week. Microsoft on Thursday will release its automatic update for Windows XP service pack 3 (SP3).

The updates are expected to hit PCs by 10 a.m. Pacific time, July 10.

"Windows XP SP3 could be released to Automatic Updates as early as Thursday," according to a Microsoft spokesman. "As with all service pack releases, Microsoft will carefully monitor the release to ensure that all customers have a good experience."

The update will not have to be reinstalled, Microsoft said.

Microsoft released XP SP3 on May 7 after a compatibility issue delayed its original April 29 release date.

Service Pack 3 adds several networking and security improvements, and compatibility with Windows Vista and Windows Server 2008 security credential providers. It also incorporates features previously available individually as separate updates, such as Microsoft Windows Imaging Component (WIC), Microsoft Management Console (MMC) 3.0, and Wi-Fi Protected Access 2.

In May, several XP users who installed XP SP3 experienced continuous re-boots.

Microsoft later said that the problem was affecting AMD-based machines with Windows XP images that were originally captured by an OE on an Intel-based machine.

"The problem is a registry value, present on images created w/ Intel processors, that causes a driver (intelppm.sys) to load at boot," according to a Microsoft Update blog entry. "When intelppm.sys attempts to load on an AMD-based system upon the install of SP3, it causes a blue screen and the continuous reboot."

Microsoft said it would add a filter to prevent the reboots.