User's Manual

Reference Thermal Solution
Thermal and Mechanical Design Guidelines 21
Figure 6. Processor Heatsink Orientation to Provide Airflow to (G)MCH Heatsink on a
Balanced Technology Extended (BTX) Platform
Top View
Balanced Technology
Extended (BTX) Thermal
Module Assembly Over
Processor
(G)MCH
Airflow Direction
Proc_HS_Orient
4.2 Mechanical Design Envelope
The motherboard component keep-out restrictions for the (G)MCH on an ATX platform
are included in
Appendix B, Figure 10. The motherboard component keep-out
restrictions for the (G)MCH on a BTX platform are included in
Figure 11.
System integrators should ensure no board or chassis components would intrude into
the volume occupied by the (G)MCH thermal solution.
4.3 Thermal Solution Assembly
The reference thermal solution for the (G)MCH for an ATX platform is shown in
Figure 7 and Appendix B and is an aluminum extruded heatsink that uses two ramp
retainers, a wire preload clip, and four custom motherboard anchors. The heatsink is
attached to the motherboard by assembling the anchors into the board, placing the
heatsink over the (G)MCH and anchors at each of the corners, and securing the plastic
ramp retainers through the anchor loops before snapping each retainer into the fin
gap. The assembly is then sent through the wave process. Post wave, the wire preload
clip is assembled using the hooks on each of the ramp retainers. The clip provides the
mechanical preload to the package. A thermal interface material (Chomerics* T710) is
pre-applied to the heatsink bottom over an area that contacts the package die.
The reference thermal solution for the (G)MCH for a BTX platform is shown in
Figure 8. The heatsink is aluminum extruded and uses a Z-clip for attach. The clip is
secured to the system motherboard via two solder-down anchors around the (G)MCH.
The clip helps to provide a mechanical preload to the package via the heatsink. A
thermal interface material (Chomerics* T710) is pre-applied to the heatsink bottom
over an area in contact with the package die.
The ATX reference thermal solution differs from the BTX reference solution because a
BTX platform requires a Support and Retention Mechanism (SRM) that helps to meet
the mechanical requirements listed in
Table 4.