Intel S2600WF Technical Product Specification page 115

Intel® Server Board S2600WF Product Family Technical Product Specification
is still present, the boost state returns once the sensor has re-initialized and the threshold violation is
detected again.
12.3.3.2 Fan Redundancy Detection
The BMC supports redundant fan monitoring and implements a fan redundancy sensor. A fan redundancy
sensor generates events when its associated set of fans transitions between redundant and non-redundant
states, as determined by the number and health of the fans. The definition of fan redundancy is
configuration dependent. The BMC allows redundancy to be configured on a per fan redundancy sensor
basis through OEM SDR records.
A fan failure or removal of hot-swap fans up to the number of redundant fans specified in the SDR in a fan
configuration is a non-critical failure and is reflected in the front panel status. A fan failure or removal that
exceeds the number of redundant fans is a non-fatal, insufficient-resources condition and is reflected in the
front panel status as a non-fatal error.
Redundancy is checked only when the system is in the DC-on state. Fan redundancy changes that occur
when the system is DC-off or when AC is removed will not be logged until the system is turned on.
12.3.3.3 Fan Domains
System fan speeds are controlled through pulse width modulation (PWM) signals, which are driven
separately for each domain by integrated PWM hardware. Fan speed is changed by adjusting the duty cycle,
which is the percentage of time the signal is driven high in each pulse.
The BMC controls the average duty cycle of each PWM signal through direct manipulation of the integrated
PWM control registers.
The same device may drive multiple PWM signals.
12.3.3.4 Thermal and Acoustic Management
This feature refers to enhanced fan management to keep the system optimally cooled while reducing the
amount of noise generated by the system fans. Aggressive acoustics standards might require a trade-off
between fan speed and system performance parameters that contribute to the cooling requirements,
primarily memory bandwidth. The BIOS, BMC, and SDRs work together to provide control over how this
trade-off is determined.
This capability requires the BMC to access temperature sensors on the individual memory DIMMs.
Additionally, closed-loop thermal throttling is only supported with DIMMs with temperature sensors.
12.3.3.5 Thermal Sensor Input to Fan Speed Control
The BMC uses various IPMI sensors as inputs to the fan speed control. Some of the sensors are IPMI models
of actual physical sensors whereas some are virtual sensors whose values are derived from physical sensors
using calculations and/or tabular information.
The following IPMI thermal sensors are used as the input to the fan speed control:
Front panel temperature sensor
•
• CPU margin sensors
DIMM thermal margin sensors
•
Exit air temperature sensor
•
• PCH temperature sensor
Onboard Ethernet controller temperature sensors
•
Add-in SAS module temperature sensors
•
• PSU thermal sensor
CPU VR temperature sensors
•
DIMM VR temperature sensors
•
1
2, 4, 5
2, 4
1, 7, 9
3, 5
3, 5
3, 8
3, 6
3, 6
3, 5
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