Intel DB75EN, Specification

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Intel Desktop Board DB75EN Technical Product Specification
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The underlying SATA functionality is transparent to the operating system. The SATA
controller can operate in both legacy and native modes. In legacy mode, standard IDE
I/O and IRQ resources are assigned (IRQ 14 and 15). In native mode, standard PCI
Conventional bus resource steering is used. Native mode is the preferred mode for
configurations using the Windows* XP and Windows 7 operating systems.
NOTE
Many SATA drives use new low-voltage power connectors and require adapters or
power supplies equipped with low-voltage power connectors.
For more information, see:
http://www.serialata.org/ .
For information about Refer to
The location of the SATA connectors Figure 11, page 45
1.6 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 via the power supply 5V STBY rail.
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 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 13 shows the location of the battery.
1.7 Legacy I/O Controller
The I/O controller provides the following features:
•
One serial port
•
One back panel parallel port (with Extended Capabilities Port (ECP) and Enhanced
Parallel Port (EPP) support)
• PS/2-style keyboard/mouse interface on the back panel
• Serial IRQ interface compatible with serialized IRQ support for PCI systems
•
Intelligent power management, including a programmable wake-up event interface
• Conventional PCI bus power management support
The BIOS Setup program provides configuration options for the I/O controller.