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Computer Group Literature Center Web Site
Functional Description
2
Video Interface
Standard SVGA analog output is available on the rear I/O panel. The video
function is provided via the Intel 82815 Graphics Memory Controller Hub
(GMCH). The BIOS must have a selection in the CMOS setup to disable
the onboard video to allow the user to use a PCI video as the primary video
controller. The BIOS must also have a selection in the CMOS setup to
disable the onboard video to allow the user to reclaim the memory for
applications without having to add another video card.
Reset
The VP22 has a circuit that monitors system power and provides the
PWROK signal to the 82801BA I/O Controller Hub2 (ICH2). This circuit
distributes the reset to the rest of the board by generating the CPU, PCI and
IDE resets. This board can also be reset by an external switch that is
connected to an onboard header.
Environmental Monitoring
The Winbond 83627HF hardware monitor device on the VP22
motherboard provides a number of useful system management features.
These features include temperature, fan and voltage monitoring. The
hardware monitor allows software to monitor voltages with its analog-to-
digital converters. An alarm sounds when the system voltage is
±
10
percent.
CPU Temperature Monitor
An internal Pentium III thermal sensor monitors microprocessor
temperature. An overtemperature condition produces an alarm signal.
Open Chassis Alarm
The VP22 implements an open chassis circuit that can latch an open
chassis event even when the system is turned off, as long as battery or
standby power is still present. The open chassis interrupt is fed into the
83627HF hardware monitor chip. This circuit can only be reset via
