Thermal Considerations
Bengal (VL-EPMe-30) Reference Manual
50
CPU Thermal Trip Points
The CPU cores in the Bengal have their own thermal sensors. Coupled with these sensors are
specific reactions to four thermal trip points. Table 27 describes the four thermal trip points.
Table 27: CPU Thermal Trip Points
Trip Point
Description
Active (Note 1)
The fan is turned on when this temperature is reached
Passive (Note 2)
At this temperature, the CPU cores throttle back to a lower speed. This
reduces the power draw and the temperature.
Critical (Note 3)
At this temperature, the operating system typically puts the board into a
sleep or other low-power state.
Maximum core temperature
The CPU turns itself off when this temperature is reached. This is a fixed
trip point and cannot be adjusted.
Notes:
1. The default value in the BIOS Setup utility for this trip point is 55 ºC.
2. The default value in the BIOS Setup utility for this trip point is 105 ºC.
3. The default value in the BIOS Setup utility for this trip point is 110 ºC.
These trip points allow maximum CPU operational performance while maintaining the lowest CPU
temperature possible. The long-term reliability of any electronic component is degraded when it is
continually run near its maximum thermal limit. Ideally, the CPU core temperatures would be kept
well below 100 ºC with only brief excursions above.
CPU temperature monitoring programs are available to run under both Windows and Linux. Table
28 lists some of these hardware monitoring programs.
Table 28: Temperature Monitoring Programs
Operating System
Program Type
Description
Windows
Core Temperature
http://www.alcpu.com/CoreTemp/
Hardware Monitor
http://www.cpuid.com/softwares/hwmonitor.html
Open Hardware Monitor
http://openhardwaremonitor.org/
Linux
lm-sensors
http://en.wikipedia.org/wiki/Lm_sensors
