Reference Thermal Solution
R
6.5.4.1Effect of Pressure on TIM Performance
As mechanical pressure increases on the TIM, the thermal resistance of the TIM decreases. This phenomenon is due to the decrease of the bond line thickness (BLT). BLT is the final settled thickness of the thermal interface material after installation of heatsink. The effect of pressure on the thermal resistance of the Honeywell* PCM45F TIM is shown in Table
Table
Pressure (psi) | Thermal Resistance (°C × in2)/W |
|
|
5 | 0.049 |
|
|
10 | 0.046 |
|
|
20 | 0.045 |
|
|
30 | 0.044 |
|
|
Note: All measured at 50 °C.
6.5.5Heatsink Clip
The retention mechanism in this reference solution includes two different types of clips; one is ramp clip and the other is wire clip. Each end of the wire clip is attached to the ramp clip that in turn attaches to anchors to fasten the overall heatsink assembly to the motherboard. See Appendix B for a mechanical drawing of the clip.
6.5.6Clip Retention Anchors
For 955X Express
24 | Intel® 955X Express Chipset Thermal/Mechanical Design Guide |