64-bit Intel Xeon Processor with 2MB L2 Cache Thermal/Mechanical Design Guidelines

Thermal/Mechanical Reference Design
30 64-bit Intel® Xeon™ Processor with 2MB L2 Cache Thermal/Mechanical Design Guidelines
The 1U CEK Intel reference thermal solution is designed to meet the Thermal Profile B for the 64-
bit Intel Xeon Processor with 2MB L2 Cache. From Table 2-2, the three-sigma (mean+3sigma)
performance of the thermal solution is computed to be 0.346 °C/W and the processor local ambient
temperature (T
LA
) for this thermal solution is 40 °C. Hence, the Thermal Profile equation for this
thermal solution is calculated as:
Equation 2-9. y = 0.346x + 40
where,
y = Processor T
CASE
value (°C)
x = Processor power value (W)
Figure 2-12 below shows the comparison of this reference thermal solution’s Thermal Profile to the
64-bit Intel Xeon Processor with 2MB L2 Cache Thermal Profile B specification. The 1U CEK
solution meets the Thermal Profile B with a 2.4 °C margin at the lower end (Pcontrol_base_B) and
a 0.9 °C margin at the upper end (TDP). However, as explained in Section 2.2.3, designing to
Thermal Profile B results in increased TCC activation and measurable performance loss for the
processor. In this case, it is estimated that up to 5% of all the processors in a population that utilizes
the 1U CEK reference solution may see TCC activation that results in a measurable performance
loss of >1.5% when running an application that consumes power equivalent to TDP.
Figure 2-11. 2U+ CEK Thermal Adherence to 64-bit Intel
®
Xeon™ Processor with 2MB L2
Cache Thermal Profile A