Really, it's a problem with the PC's clock.

Really, it's a problem with the PC's clock.

The Millennium Bug in PC hardware is caused by an error of logic in the PC's real-time clock (RTC). This is a small chip in your computer that ticks 18 times every second to enable it to maintain the time and date. the chip takes its power from a battery when the computer is switched off. This enables it to keep the date and time even when your PC is not in use. The problem occurs when the RTC does not roll over the century byte correctly, so 1999 becomes 1900 instead of 2000.

If your PC is more than two years old, it is almost certainly to be non-compliant.

When PC manufacturers became aware of the problem, the most common method was to amend the Bios of the PC so that it can detect the bug after it happens and then fix it. When a manufacturer puts this patch into their Bios, they call it a "Millennium compliant Bios".

"Millennium compliant Bios" means that your PC is alright as long as you switch it off in 1999 and switch it back on the year 2000.

An extended form of this patch has found its way into some Bios programs. With this as well as fixing the RTC at boot-up, the Bios will detect if any application uses the Bios to retrieve the data.