Intel Core2 Duo Desktop Processor, Intel Pentium Processor, and Intel Pentium 4 Processor 6x1 Sequence
ATX Thermal/Mechanical Design Information
54 Thermal and Mechanical Design Guidelines
Table 8. ATX Target Heatsink Performance in 775_VR_CONFIG_06 65 W Processor
Processor Thermal Performance
Ψca (Mean + 3σ)
T
A
Assumption
Notes
Intel
®
Core™2 Duo desktop processor E6000
sequence with 4 MB cache
0.31 °C/W 40 °C 1, 2
Intel
®
Core™2 Duo desktop processor
E6000/E4000 sequence with 2 MB cache
0.33 °C/W 40 °C 1, 2
Intel
®
Pentium
®
Dual Core processor E2000
sequence
0.33 °C/W 40 °C 2
Intel
®
Pentium
®
4 processor 6x1 sequence 0.37 °C/W 40 °C 2
NOTE:
1. The difference in Ψ ca between the Intel
®
Core™2 Duo desktop processor E6000/E4000
sequence with 4 MB cache and 2 MB cache is due to a slight difference in the die size.
2. Performance targets (Ψ ca) as measured with a live processor at TDP.
6.1.2 Acoustics
To optimize acoustic emission by the fan heatsink assembly, Intel recommends the
use of a thermistor controlled variable speed fan. A variable speed fan allows higher
thermal performance at higher fan inlet temperatures (T
A
) and lower thermal
performance with improved acoustics at lower fan inlet temperatures. The required
fan speed necessary to meet thermal specifications can be controlled by the fan inlet
temperature and should comply with requirements below:
Table 9. Acoustic Results
Fan Speed
RPM
Thermistor
Set Point
Acoustic Thermal Performance Ψca Notes
2300 High
T
A
= 40 °C
4.1 BA 0.31 °C/W (Intel
®
Core™2 Duo Processor -
4 MB)
0.33 °C/W (Intel
®
Core™2 Duo Processor -
2 MB)
0.33 °C/W (Intel
®
Pentium Dual-Core
E2000 sequence)
0.37 °C/W (Intel
®
Pentium
®
6x1 sequence)
1000 Low
T
A
= 28 °C
3.3 BA 0.49 °C/W (Intel
®
Core™2 Duo Processor -
4 MB)
0.51 °C/W (Intel
®
Core™2 Duo Processor -
2 MB)
0.51 °C/W (Intel
®
Pentium Dual-Core
E2000 sequence)
0.56 °C/W (Intel
®
Pentium
®
6x1 sequence)
Thermal
Design
Power, Fan
speed
limited by
the fan hub
thermistor
1000 Low
T
A
= 28 °C
3.3 BA Minimum
fan speed
Note: Acoustic performance is defined in terms of measured sound power (LwA) as defined
in ISO 9296 standard, and measured according to ISO 7779.