Specifications

QSSC-S4R Technical Product Specification BIOS Initialization
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16.9.1.4 Closed Loop Thermal Throttling (CLTT)
QSSC-S4R support Fan Speed Control (FSC) in Closed Loop Thermal Throttling (CLTT) fashion. OLTT is NOT
supported. CLTT is enabled by default by BIOS. Also in QSSC-S4R only RDIMM are supported. If RDIMM with a failed
Thermal Sensor is detected CLTT will not be enabled and BIOS error manager will show that error.
For a very detailed description on the thermal sensors, thermal zones, zone aggregation and fan domains please refer
to the QSSC-S4R Fan Speed Control and Thermal Management Platform Architecture Specification, rev 1.0.
16.9.2 Processor Thermal Management
The processors implement a methodology for managing processor temperatures through processor throttling. The
temperature used to regulate the processors is calculated using the following two components:
x Tcontrol offset (BMC reads this using PECI).
x Tcontrol base (BMC retrieves this value from SDR).
The BMC uses these two Tcontrol values to regulate processor thermal characteristics according to the user-selected
fan profile.
See the
Nehalem Processor Family BIOS Writer’s Guide for more information.
16.9.3 Node Power Thermal Management (NPTM) or Node Manager (NM)
The QSSC-S4R BIOS has set up Intel
®
Intelligent Power Node Manager 1.5 compatible interfaces to allow greater
processor thermal and power control.