Intel CELERON 200 - Manual (Page 31)

Thermal Metrology
Thermal and Mechanical Design Guidelines 31
measurements will reveal a highly non-uniform temperature distribution across the
inlet fan section.
For passive heatsinks, thermocouples should be placed approximately 3 mm away
from the heatsink as shown in Figure 12.
Note: Testing an active heatsink with a variable speed fan can be done in a thermal
chamber to capture the worst-case thermal environment scenarios. Otherwise, when
doing a bench top test at room temperature, the fan regulation prevents the heatsink
from operating at its maximum capability. To characterize the heatsink capability in
the worst-case environment in these conditions, it is then necessary to disable the fan
regulation and power the fan directly, based on guidance from the fan supplier.
Figure 11. Locations for Measuring Local Ambient Temperature, Active Heatsink
NOTE: Drawing Not to Scale