Real-Time Clock Subsystem - Intel BLKDH55TC Product Manual

Desktop Board Features

Real-Time Clock Subsystem

A coin-cell battery (CR2032) powers the real-time clock and CMOS memory. When
the computer is not plugged into a wall socket, the battery has an estimated life of
three years. When the computer is plugged in, the standby current from the power
supply extends the life of the battery.
The clock is accurate to ± 13 minutes/year at 25 ºC with standby power applied by the
power supply.
NOTE
If the battery and AC power fail, date and time values will be reset and the user will be
notified during the POST.
When the battery voltage drops below a certain level, the BIOS Setup program
settings stored in CMOS RAM (for example, the date and time) might not be accurate.
Replace the battery with an equivalent one. Go to page 56 for instructions on how to
replace the battery.
25