EKF PC7-FESTIVAL, Руководство пользователя

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User Guide • PC7-FESTIVAL • CompactPCI® PlusIO CPU Board
Thermal Considerations
In order to avoid malfunctioning of the PC7-FESTIVAL, take care of appropriate cooling of the
processor and system, e.g. by a cooling fan suitable to the maximum power consumption of the
CPU chip actually in use. The processor contains digital thermal sensors (DTS) that are readable via
special CPU registers or via PECI bus. DTS allows to get the temperatures of each CPU core
separately.
Two further temperature sensors, one of it located in the system hardware monitor NCT7491,
allows for acquisition of the boards surface temperature and the thermal state of the onboard
system memory channel. Beside this the NCT7491 also keeps a PECI 3.0 master for CPU DTS
monitoring and supervises most of the supply voltages. A suitable software on Microsoft
Windows® systems to display both, the temperatures as well as the supply voltages, is Speedfan,
which can be downloaded from the web. After installation, both temperatures and voltages can
be observed permanently from the Windows® taskbar.
The PC7-FESTIVAL 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 (>20m
3
/h
or 2m/s (400LFM) 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 3m/s (600LFM) or more.
The table showing the supported processors above give also the maximum power consumption
(TDP) 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 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 800MHz. Additional a reduction of the graphics core clock (down to
350MHz) and voltage is possible. This leads to an obvious reduction of power consumption
resulting in less heating.
A further way to reduce power consumption is achieved by Intels voltage regulators belonging to
the IMVP8 standard. These regulators allows the processor to regulate the voltages to the cores,
graphics, system agent and other units separately depending on their performance needs. Parts
that are currently idle may switched off to save power.
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