Intel Core2 Duo Desktop Processor, Intel Pentium Processor, and Intel Pentium 4 Processor 6x1 Sequence

Intel® Enabled Balanced Technology Extended (BTX) Reference solution
44 Thermal and Mechanical Design Guidelines
Figure 10. Effective TMA Fan Curves with Reference Extrusion
0.000
0.050
0.100
0.150
0.200
0.250
0.300
0.350
0.400
0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0
Airflow (cfm)
dP (in. H2O)
Reference TMA @ 5300 RPM
Reference TMA @ 2500 RPM
Reference TMA @ 1200 RPM
5.1.4 Voltage Regulator Thermal Management
The BTX TMA is integral to the cooling of the processor voltage regulator (VR). The
reference design includes a flow partitioning device to ensure an appropriate airflow
balance between the TMA and the VR as well as provide sufficient downstream airflow
to the chipset.
The BTX thermal management strategy relies on the Thermal Module to provide
effective cooling for the voltage regulator (VR) chipset and system memory
components on the motherboard. The Thermal Module is required to have features
that allow for airflow to bypass the heatsink and flow over the VR region on both the
primary and secondary sides of the board. The following requirements apply to VR
cooling.
Table 5. VR Airflow Requirements
Item Target
Minimum VR bypass airflow for 775_VR_CONFIG_06 processors 2.4 CFM
NOTE:
1. This is the recommended airflow rate that should be delivered to the VR when the VR
power is at a maximum in order to support the 775_VR_CONFIG_06 processors (Intel
®
Core™2 Duo desktop processor E6000/E4000 sequence, Intel
®
Pentium
®
Dual Core
processor E2000 sequence, and Intel
®
Pentium
®
4 processor 6x1 sequence) at TDP
power dissipation, and the chassis external environment temperature is at 35 ºC. Less
airflow is necessary when the VR power is not at a maximum or if the external ambient
temperature is less than 35 ºC.
2. This recommended airflow rate is based on the requirements for the Intel
®
965 Express
chipset family.