In a nutshell, the Y2K problem is in the way computers store the date. Most dates are stored as 01/31/97. When year 2000 comes around, the date would be stored as 01/01/00. The problem is, does 00 mean 2000 or does it mean 1900? A person, with common sense, looking at 01/01/00 will realized it's January 1, 2000, not January 1, 1900. But a computer doesn't have any common sense; it'll do what it's programmed to.

Here's a technical explanation of the problem taken from NSTL Y2K website:

The IBM AT is the standard most "x86 based industry standard personal computers" apply. The IBM AT utilizes a Motorola MC146818 Real-Time Clock plus RAM (RTC) chip for maintaining the date and time while the computer is off. IBM personal computers prior to the AT have no real time clock; thus, the date and time has to be manually set every time the computer is booted. With the IBM AT, users no longer have to manually enter the date and time.

Unfortunately, the Motorola MC146818 RTC uses only 8-bits of information to report the year. Eight bits is sufficient to hold the last two digits of a year in packed BCD format. So 1997 is reported solely as 97. Since the MC146818 also contains non-volatile memory, IBM specified location 32h in the memory to hold century information. By combining the century data with the year data, software can obtain a full 4-digit year. Please note that the century is not manipulated by the RTC - location 32h is used only for storage of information.

When the Year 2000 occurs, the RTC reports the year as '00' and the century in RTC memory will contain '19.' Combining the full 4-digit year yields 1900, not 2000.

The following PREMIO systems are certified by NSTL or self-certified by PREMIO. We have a three year license from NSTL to perform in-house testing for Y2K.

Windows NT 4.0 Workstation

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