Microsoft have released a post-sp2 fix for an issue where a limited number of systems running a BIOS without production support for Intel Pentium 4 and Intel Celeron D processors based on Prescott C-0 stepping can potentially hang on Windows XP Service Pack 2 installation. You can download the update here (http://www.microsoft.com/downloads/details.aspx?FamilyID=9b99c199-5d75-454f-ae07-b620727be8d8&DisplayLang=en).