Xeon-Phi-Coprocessor-Datasheet

Table 3-3 shows thermal specifications of components present on the SE10X/7120X
and 7120D/5120D boards.
Table 3-3.
Component Thermal Specification on SE10X/7120X and 7120D/5120D
Component
Thermal specification
Coprocessor T case ≤ 95°C
GDDR T case ≤ 85°C
VR FET T junction ≤ 150°C 1
VR Inductor T body ≤ 100°C
Notes:
1. While this is the component specification, on the passive and active Intel ® Xeon Phi coprocessor
products, the junction temperature is limited to 135°C in order to prevent damage to the PCB.
3.4.1.1 VR Temperature and Thermal Throttling
Some thermal sensors on the coprocessor are located in the field of the VR inductors
and FETs that drive power to the coprocessor silicon, GDDR and other circuitry
(Figure 3-15). These sensors continuously monitor the temperature of the circuit
board. If the temperature reaches or exceeds 105° C, an interrupt will be sent to the
SMC. In response to this interrupt, the SMC will assert PROCHOT to the coprocessor
which in turn will force the coprocessor frequency to drop to the minimum supported
value (approximately 600MHz). This frequency drop will reduce the power dissipation
of the card and should allow the VR components to cool down. Once the temperature
has dropped below 105° C, the VR controller will send a message to the SMC to deassert
PROCHOT. This will allow the coprocessor to return to the normal high frequency
operating point.
Figure 3-15 7120D/5120D VR Thermal Sensors for Custom Cooling Consideration
VR thermal
sensor
VR thermal
sensor
Intel Xeon Phi
Coprocessor
Silicon
VR thermal
sensor
Intel ® Xeon Phi Coprocessor Datasheet
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Document ID Number: 328209 003EN