Connector/Header Locations and Pin-outs
Intel® Server Board S3420GP TPS
Revision
2.4
Intel order number E65697-010
80
7.4.1
Power Button
The BIOS supports a front control panel power button. Pressing the power button initiates a
request that the Integrated BMC forwards to the ACPI power state machines in the chipset. It is
monitored by the Integrated BMC and does not directly control power on the power supply.
Power Button — Off to On
The Integrated BMC monitors the power button and the wake-up event signals from the
chipset. A transition from either source results in the Integrated BMC starting the power-
up sequence. Since the processor are not executing, the BIOS does not participate in
this sequence. The hardware receives the power good and reset signals from the
Integrated BMC and then transitions to an ON state.
Power Button — On to Off (Operating system absent)
The System Control Interrupt (SCI) is masked. The BIOS sets up the power button event
to generate an SMI and checks the power button status bit in the ACPI hardware
registers when an SMI occurs. If the status bit is set, the BIOS sets the ACPI power
state of the machine in the chipset to the OFF state. The Integrated BMC monitors
power state signals from the chipset and de-asserts PS_PWR_ON to the power supply.
As a safety mechanism, if the BIOS fails to service the request, the Integrated BMC
automatically powers off the system in 4 to 5 seconds.
Power Button — On to Off (Operating system present)
If an ACPI operating system is running, pressing the power button switch generates a
request using SCI to the operating system to shut down the system. The operating
system retains control of the system and the operating system policy determines the
sleep state into which the system transitions, if any. Otherwise, the BIOS turns off the
system.
7.4.2
Reset Button
The platform supports a front control panel reset button. Pressing the reset button initiates a
request forwarded by the Integrated BMC to the chipset. The BIOS does not affect the behavior
of the reset button.
7.4.3
NMI Button
The Intel
®
S3420GP Server Board family BIOS does not support the NMI button.
7.4.4
System Status Indicator LED
The Intel
®
Server Board S3420GP that uses the Intel
®
Xeon
®
Processor 3400 Series has a
system status indicator LED on the front panel. This indicator LED has specific states and
corresponding interpretation as shown in the following table.
Table 46. System Status LED Indicator States
Color
State
Criticality
Description
Green
Solid on
Ok
System booted and ready
