Microsoft Year 2000 Readiness Disclosure & Resource Center

Windows Operating System Interactions with BIOS and Real Time Clock

The RTC and BIOS functionally support each other so it is advisable to view their Year 2000 readiness as a combined unit. Most RTC rollover issues are remedied by the BIOS, while still others are remedied by the operating system.

In older PCs, the BIOS software may not automatically roll over the century. In that case, the century register in the RTC will remain at "19" when the date should roll from 1999 to 2000. Some PCs have BIOS that do not rec