My previous desktop PC had boot problems when the CMOS battery voltage dropped much below 3V yet the BIOS date was correct. Replace the CMOS battery...
Whilst I do not see the relevance of the Compatibility pack to this thread, since it has been mentioned I'd like to point out that the download link...
One other point, if desiring to open the newer .docx files in Office 2000, 2002/XP or 2003 one can add the Compatibility Pack to the older programs....