Different computers react differently when the date rolls over at midnight from December 31, 1999 to January 1, 2000. Some computers update the date correctly, some do not. The Date is a function of the Real Time Clock (RTC) which can be a one chip solution or spread among several chips on a motherboard. The RTC may or may not be aware of the year 2000 rollover. Current systems have an updated BIOS that knows how to correctly roll over the date on the year 2000. Older BIOSes may change the year to a different year, depending on the BIOS at the time. If the BIOS does not roll the date over, the customer will need to enter the BIOS once, on or after January 1, 2000 and set year correctly. This is no more complicated than changing a clock for daylight savings time and only needs to be done once.

        Modern operating systems, such as Windows 95 or 98, Windows NT, and OS/2 read the date from the BIOS, once, when the operating system first starts up. After that they have their own time and date keeping functions. These operating systems are aware of the year 2000 rollover and handle it correctly, even if the BIOS does not. If the BIOS does not handle the year 2000 rollover correctly, the BIOS date and the operating system's date will not match. If this is the case, a power down at the earliest possible time after the year 2000 rollover should be done to adjust the date in the BIOS.

        A well written program gets it's date from an operating system call. It is not a good programming practice to read the date from the RTC. Specialized software, such as industrial controllers, PBXes, voice mail systems, etc. may be running in their own operating system environment. This software should normally read the date from the BIOS and not the RTC.

If a DFI motherboard's BIOS date is 05/09/1997 or newer, it has code in the BIOS to adjust the date if the RTC does not roll the date correctly.
If the BIOS date is older than 05/09/1997, DFI recommends testing the motherboard using the following method:

        Exit all programs and shut the system down. Turn the computer off and then back on. When prompted, enter the BIOS setup (consult the motherboard manual for details on how to do this). Change the date to December 31, 1999. Change the time to a minute or less before midnight. Watch the rollover and observe what the date changes to. If the date rolls over correctly, you will have no problems with the system. If the date does not roll over correctly, note this and put it in a safe place. A sticker on the system case with the test results may be a good idea. If the date did not roll over correctly, set the date to December 31, 2000. Change the time to a minute or less before midnight. Watch the rollover and observe the results. If the date rolls over to 2001 correctly, then you will only have to change the date once, after the year 2000 rollover. It is probably a good idea to check a few leap year rollovers, such as February 28, 2000, February 28, 2004, February 29, 2008, etc. In the unlikely event that a system fails the leap year rollover tests or the December 31, 2000 test, make a note, it may be easiest to replace such a motherboard with a newer one. At this time we are not aware of any systems that fail all of the above tests, however we have not tested all of our older products.

        At this time we can not recommend any software "Year 2000" tests. These programs generally read the RTC directly, which will normally fail, or they look for a specific RTC brand/model. Many of the companies that put this software out are well meaning, but a few are trying to sell software products or a service. DFI can only recommend the above test procedure.

        DFI recommends checking any software that uses date functions to determine if the date is being read from the correct location (the operating system) and that the software is aware of the rollover for the year 2000. If you have any further questions or concerns, please direct them to your nearest DFI representative.