Motherboard Features
12
Real-Time Clock
The motherboard has a time-of-day clock and 100-year calendar that will rollover to 2000 at the
turn of the century. A battery on the motherboard keeps the clock current when the computer is
turned off.
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NOTE
The recommended method of accessing the date in systems with Intel motherboards is indirectly
from the Real-Time Clock (RTC) via the BIOS. The BIOS on Intel motherboards and baseboards
contains a century checking and maintenance feature that checks the least two significant digits of
the year stored in the RTC during each BIOS request (INT 1Ah) to read the date and, if less than
80 (i.e., 1980 is the first year supported by the PC), updates the century byte to 20. This feature
enables operating systems and applications using the BIOS date/time services to reliably
manipulate the year as a four-digit value.
For more information on proper date access in systems with Intel motherboards please see
http://support.intel.com/support/year2000/paper.htm
Universal Serial Bus (USB) Support
The motherboard has two USB ports. You can connect two USB peripheral devices directly to the
computer without an external hub. To attach more than two devices, connect an external hub to
either of the built-in ports. The motherboard supports the standard universal host controller
interface (UHCI) and takes advantage of standard software drivers written to be compatible with
UHCI. The USB features the following:
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Support for hot swapping Plug and Play devices
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Support for self-identifying peripherals
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Support for up to 127 physical devices
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Guaranteed bandwidth and low latencies appropriate for telephony, audio, and other
applications
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NOTE
Computer systems that have an unshielded cable attached to a USB port may not meet FCC
Class B requirements, even if no device or a low-speed USB device is attached to the cable. Use a
shielded cable that meets the requirements for a high-speed USB device.
AGP
The AGP is a high-performance interconnect for graphics-intensive applications, such as 3D
graphics. AGP is independent of the PCI bus and is intended for exclusive use with graphical
display devices. AGP provides these features:
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Pipelined memory read and write operations that hide memory access latency
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Demultiplexing of address and data on the bus for near 100 percent bus efficiency
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AC timing for 133 MHz data transfer rates, allowing real data throughput in excess of
500 MB/sec