Intel Pentium 4 Processor in the 478-Pin Package Thermal Design Guidelines

Intel
®
Pentium
®
4 Processor in the 478-Pin Package Thermal Design Guidelines
R
38 Design Guide
3.1.1.3 Reference Heatsink Thermal Validation
The Intel reference heatsink is validated within specific boundary conditions based on the
methodology described section 2.3, and using a thermal test vehicle (refer to section 2.3.4).
Testing is done on bench top test boards at ambient lab temperature. In particular, for the reference
heatsink, the Plexiglas* barrier is installed 3 inches above the motherboard (refer to section 2.3.2).
The test results are reported in terms of performance on real parts (using the thermal test vehicle
correction factor), and of mean + 3σ value.
3.1.2 Fan Performance for Active Heatsink Thermal Solution
The fan power requirement for proper operation is a maximum current of 740 mA at 12 V.
For active thermal solutions, the fan should demonstrate a functional lifetime of 40,000 hours. In
addition, the fan should demonstrate performance to the reliability criteria outlined in Table 4.
Table 4. Fan Performance Recommendation
Test Requirement Pass/Fail Criteria
Thermal Cycling -5 °C to +70 °C, 500 cycles visual check
1
RPM check
2
Humidity 85% relative humidity / 55 °C, 1000 hours visual check
1
RPM check
2
Power Cycling 7,500 on/off cycles with each cycle specified as
3 minutes on, 2 minutes off 70 °C
visual check
1
RPM check
2
NOTES:
1. Visual check: Labels, housing and connections are all intact.
2. RPM check: No fan RPM changes of greater than 20%, following test.