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

Intel® Enabled Balanced Technology Extended (BTX) Reference solution
42 Thermal and Mechanical Design Guidelines
5.1.2 Acoustics
To optimize acoustic emission by the fan heatsink assembly, the reference design
implements a variable speed fan. A variable speed fan allows higher thermal
performance at higher fan inlet temperatures (T
A
) and the appropriate 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 4. Acoustic Targets
Fan
Speed
RPM
Thermistor
Set Point
Acoustic Thermal Performance Ψca Notes
~ 5300 High
T
A
≥ 35 °C
≤ 6.4 BA • 0.38 °C/W (Intel
®
Core
™
2 Duo
processors - 4 MB)
• 0.40 °C/W (Intel
®
Core
™
2 Duo
processors - 2 MB)
• 0.40 °C/W (Intel
®
Pentium
Dual-Core E2000 sequence)
• 0.44 °C/W (Intel
®
Pentium
®
4
processor 6x1 sequence)
Case 1:
Thermal Design Power
Maximum fan speed
100% PWM duty cycle
~ 2500 Low
T
A
= 23 °C
No Target
Defined
• 0.56 °C/W (Intel
®
Core
™
2 Duo
processors - 4 MB)
• 0.58 °C/W (Intel
®
Core
™
2 Duo
processors - 2 MB)
• 0.58 °C/W (Intel
®
Pentium
Dual-Core E2000 sequence)
• 0.63 °C/W (Intel
®
Pentium
®
4
processor 6x1 sequence)
Case 2
Thermal Design Power
System (PSU, HDD, TMA)
Fan speed limited by the
fan hub thermistor
~ 1400 Low
T
A
= 23 °C
≤ 3.4 BA • ~0.87 °C/W (Intel
®
Core
™
2
Duo processors - 4 MB)
• ~0.89 °C/W (Intel
®
Core
™
2
Duo processors - 2 MB)
• ~0.89 °C/W (Intel
®
Pentium
Dual-Core E2000 sequence)
• ~0.93 °C/W (Intel
®
Pentium
®
4
processor 6x1 sequence)
Case 3
50% Thermal Design Power
TMA Only
~ 1400 Low
T
A
= 23 °C
≤ 4.0 BA • ~0.87 °C/W (Intel
®
Core
™
2
Duo processors - 4 MB)
• ~0.89 °C/W (Intel
®
Core
™
2
Duo processors - 2 MB)
• ~0.89 °C/W (Intel
®
Pentium
Dual-Core E2000 sequence)
• ~0.93 °C/W (Intel
®
Pentium
®
4
processor 6x1 sequence)
Case 3
50% Thermal Design Power
System (PSU, HDD, TMA)
NOTE:
1. Acoustic performance is defined in terms of measured sound power (LwA) as defined in
ISO 9296 standard, and measured according to ISO 7779.
2. Acoustic testing will be for the TMA only when installed in a BTX S2 chassis for Case 1
and 3