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C.1 Thermal Requirements
The cPB-4612 is equipped with an integrated heatsink for cooling the processor module. The maximum
processor core temperature must not exceed 100°C. The heatsink allows a maximum ambient air
temperature of 50°C with 200 linear feet per minute (LFM) of airflow. The maximum power dissipation of
the CPU is 25 W at 1.2 GHz and 1.20V.
CAUTION: External airflow must be provided at all times during operation to avoid damaging
the CPU. DTI strongly recommends the use of a fan tray below the card rack to supply the
external airflow.
The "Thermal Requirements" table below shows the relationship between ambient air temperature, board
temperature, and processor core temperature.
Thermal Requirements
External Ambient
Air Temperature (
°C)
Temperature
Around the Board (°C)
Pentium M processor
Core Temperature (°C)
0 13 44
5 18 49
10 22 54
15 27 60
20 33 65
25 37 69
30 42 74
35 47 79
40 52 84
45 57 89
50 63 95
55 68 100 = maximum
C.2 Temperature Monitoring
Because reliable long-term operation of the cPB-4612 depends on maintaining proper temperature, DTI
strongly recommends verifying the operating temperature of the processor module and processor core in
the final system configuration.
The Pentium 4 processor incorporates an on-die thermal diode that can be used to monitor the
processor's die temperature. The cPB-4612 includes an ADM 1026 Hardware Monitor to check the die
temperature of the processor for thermal management purposes.