Intel X3350 - Xeon 2.66 Ghz 12M L2 Cache 1333MHz FSB LGA775 Quad-Core Processor, Руководство по конструкции

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Thermal Solutions
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
Thermal/Mechanical Design Guide August 2010
59 Order Number: 323107-002US
7.5 Thermal Design
7.5.1 Thermal Characterization Parameter
The case-to-local ambient Thermal Characterization Parameter (
Ψ
CA
) is defined by:
Equation 7-1.
Ψ
CA
= (T
CASE
- T
LA
) / TDP
Where:
T
CASE
= Processor case temperature (°C). For T
CASE
specification see
Section 6 .
T
LA
= Local ambient temperature in chassis at processor (°C).
TDP = TDP (W) assumes all power dissipates through the integrated heat
spreader. This inexact assumption is convenient for heatsink design.
TTVs are often used to dissipate TDP. Correction offsets account for
differences in temperature distribution between processor and TTV.
Equation 7-2.
Ψ
CA
=
Ψ
CS
+
Ψ
SA
Where:
Ψ
CS
= Thermal characterization parameter of the TIM (°C/W) is dependent
on the thermal conductivity and thickness of the TIM.
Ψ
SA
= Thermal characterization parameter from heatsink-to-local ambient
(°C/W) is dependent on the thermal conductivity and geometry of the
heatsink and dependent on the air velocity through the heatsink fins.
Figure 7-5 illustrates the thermal characterization parameters.
Figure 7-5. Processor Thermal Characterization Parameter Relationships