Preload Degradation Under Bake Conditions - Intel 5400 Series Design Manuallines

Heatsink Clip Load Methodology
(often on the order of 3 minutes). The time zero reading should be taken at the end
of this settling time.
5. Record the preload measurement (total from all three load cells) at the target time
and average the values over 10 seconds around this target time as well, i.e. in the
interval for example over [target time – 5 seconds; target time + 5 seconds].
C.2.5

Preload Degradation under Bake Conditions

This section describes an example of testing for potential clip load degradation under
bake conditions.
1. Preheat thermal chamber to target temperature (45 ºC or 85 ºC for example).
2. Repeat time-zero, room temperature preload measurement.
3. Place unit into preheated thermal chamber for specified time.
4. Record continuous load cell data as follows:
Sample rate = 0.1 Hz for first 3 hrs
Sample rate = 0.01 Hz for the remainder of the bake test
5. Remove assembly from thermal chamber and set into room temperature conditions
6. Record continuous load cell data for next 30 minutes at sample rate of 1 Hz.
Quad-Core Intel® Xeon® Processor 5400 Series TMDG
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