User Guide CCM-BOOGIE • High Performance Core
TM
2 Duo 3U
CompactPCI
®
CPU Board
© EKF -19- ekf.com
Thermal Considerations
In order to avoid malfunctioning of the CCM-BOOGIE, take care of appropriate cooling of the
processor, GMCH and system, e.g. by a cooling fan suitable to the maximum power consumption of
the CPU chip actually in use. Please note, that the processors die temperature is steadily measured by
a special controller (ADT7421), attached to the onboard SMBus
®
(System Management Bus). The
processor also contains a digital thermal sensor (DTS) that is readable via special CPU registers. DTS
allows to get the temperatures of each CPU core separately.
Two further temperature sensors located in the system hardware monitor LM87 allows for acquisition
of the boards surface temperature and the thermal state of the onboard system memory channel.
Beside this the LM87 also monitors most of the supply voltages. A suitable software to display both,
the temperatures as well as the supply voltages, is MBM (Motherboard Monitor), which can be
downloaded from the web. After installation, both temperatures and voltages can be observed
permanently from the Windows taskbar.
The CCM-BOOGIE is equipped with a passive heatsink. Its height takes into account the 4HP limitation
in mounting space of a
CompactPCI
board. In addition, a forced vertical airflow through the system
enclosure (e.g. bottom mount fan unit) is strongly recommended (>15m
3
/h or 200LFM around the
CPU slot). Be sure to thoroughly discuss your actual cooling needs with EKF. Generally, the faster the
CPU speed the higher its power consumption. For higher ambient temperatures, consider increasing
the forced airflow to 400 or 600LFM.
The table showing the supported processors above give also the maximum power consumption (TDP
= Thermal Design Power) of a particular processor. Fortunately, the power consumption is by far
lower when executing typical Windows or Linux tasks. The heat dissipation increases when e.g.
rendering software like the Acrobat Distiller is executed.
The Core
TM
2 Duo processors support Intel's Enhanced SpeedStep® technology. This enables dynamic
switching between multiple core voltages and frequencies depending on core temperature and
currently required performance. The processors are able to reduce their core speed and core voltage
in multiple steps down to 1200MHz. Furthermore they can reduce their FSB clock speed to half the
frequency. This leads to an obvious reduction of power consumption resulting in less heating. This
mode of lowering the processor core temperature is called TM2 (TM=Thermal Monitor).
Another way to reduce power consumption is to modulate the processor clock. This mode (TM1) is
achieved by actuating the 'Stop Clock' input of the CPU. A throttling of 50% e.g. means a duty cycle
of 50% on the stop clock input. However, while saving considerable power consumption, the data
throughput of the processor is also reduced. The processor works at full speed until the core
temperature reaches a critical value. Then the processor is throttled by 50%. As soon as the high
temperature situation disappears the throttling will be disabled and the processors runs at full speed
again.
A similar feature is embedded within the Graphics and Memory Controller (GMCH) GS45. An on-die
temperature sensor is used to protect the GMCH from exceeding its maximum junction temperature
(T
J,max
=100°C) by reducing the memory bandwidth.
These features are controllable by BIOS menu entries. By default the BIOS of the CCM-BOOGIE enables
mode TM2 which is the most efficient.
