Thermal Interface Material; Emc Shield; Table 6. Suggested Thermal Interface Materials - AMD Athlon 64 Thermal Design Manual

26633 Rev. 3.03 September 2003

2.6.6 Thermal Interface Material

AMD evaluates thermal interface materials for use with its processors. A list of suggested
materials is provided in Table 6.

Table 6. Suggested Thermal Interface Materials

Manfufacturer
Bergquist
Shin Etsu
Shin Etsu
Shin Etsu
Thermoset, Lord CPD
The heatsink makes contact with the top surface of the processor package utilizing the thermal
interface material between the processor lid and the heatsink. AMD recommends using a high-
performance grease such as those listed in Table 6. AMD does not recommend using phase-
change materials between the heatsink and the processor.
Phase-change materials develop high adhesion forces between the heatsink and processor when
the material is in the solid phase. This strong adhesive force may cause the processor to stick to
the heatsink. During heatsink removal, this strong adhesive force may cause the processor to be
removed from the socket while it is locked, and this action may result in damage to the socket or
to the processor pins.
The heatsink manufacturer may apply the grease to the heatsink. If this procedure is done, a
protective cover should be used to prevent contamination of the interface material. Additionally,
most grease should be applied in a 34–35 mm square that is 0.06–0.08 mm thick. This amount of
grease has provided good coverage of the processor lid while not being excessive. Grease may
flow over the edges of the processor and reach the socket if excessive amounts are applied. This is
not desirable.

2.6.7 EMC Shield

Because of the high clock frequencies of the AMD Opteron and AMD Athlon 64 processors, an
EMC shield has been designed and incorporated into the thermal solution. This shielding is a
component that may or may not be necessary for meeting regulatory agency requirements,
depending on the system. However, the shielding has been designed as a component that can be
added to the heatsink assembly either during assembly of the heatsink components or during final
assembly of the system. The heatsink retention frame has features for aligning and retaining the
EMC shield.
Chapter 2 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements
Preliminary Information
AMD Athlon™ 64 and AMD Opteron™ Processors
Interface Material
TIC-3000
G751
X23-7762
X23-7783D
TC-350
Thermal Design Guide
Material Type
Grease
Grease
Grease
Grease
Grease
Application
Processor to heatsink
Processor to heatsink
Processor to heatsink
Processor to heatsink
Processor to heatsink
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