DG31GL Technical Product Specification

Intel Desktop Board DG31GL Technical Product Specification
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1.7 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 3.3 VSB applied.
 NOTE
If the battery and AC power fail, custom defaults, if previously saved, will be loaded
into CMOS RAM at power-on.
When the 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.
Figure 1 on page 12 shows the location of the battery.
1.8 Legacy I/O Controller
The Winbond W83627DHG-B Legacy I/O controller provides the following features:
• Serial IRQ interface compatible with serialized IRQ support for PCI Conventional
bus systems
• Serial port via an onboard header
• PS/2-style mouse and keyboard interfaces
• Intelligent power management, including a programmable wake-up event interface
• PCI Conventional bus power management support
The BIOS Setup program provides configuration options for the I/O controller.
1.8.1 Keyboard and Mouse Interface
PS/2 keyboard and mouse connectors are located on the back panel.

NOTE
The keyboard is supported in the bottom PS/2 connector and the mouse is supported
in the top PS/2 connector. Power to the computer should be turned off before a
keyboard or mouse is connected or disconnected.
For information about Refer to
The location of the keyboard and mouse connectors Figure 9, page 41