Table of Contents
Advertisement
Product Specifications
ambient air for the ICH8 component in a BTX system is projected to be approximately 55°C. For
BTX platforms that have similar boundary conditions to what is stated above, ICH8 does not require
a heatsink.
Note that the local ambient air temperature for BTX is a projection based on anticipated
power increases on a 2005 platform and are subject to change in the next revision of this
document.
It is important to note, however, that since the ICH8 package has a molded plastic encapsulant, and
because plastic is such a poor heat conductor, the relative importance of the motherboard heat
transfer characteristics increases. The heat transfer capability of the motherboard in the area of the
ICH8 should be characterized. Knowledge of these heat transfer paths can be used to determine if
an ICH8 heatsink is required.
In addition, high power PCI Express* graphic cards may alter the local ambient temperature as well
as the airflow patterns in the vicinity of the chipset. Systems that have interface utilization less than
that of the TDP configuration may be at power levels that may not require a heatsink.
In conclusion, thermal validation should be performed in your anticipated system environment, in
particular measuring the ICH8 case temperature to ensure it does not exceed its maximum case
temperature specification. To evaluate the capability of your system for cooling the ICH8, the
following system level tests are suggested to assess ICH8 case temperature compliancy:
1. Shipping configuration(s) with expected end user add-in cards and I/O peripherals installed.
2. All available slots and IO ports populated (only worst case if all I/O is fully populated including
SATA, USB, etc.).
For completeness, both room ambient conditions (approximately 23 °C, to simulate impact of fan
speed control) and worse case maximum external temperature (35 °C) conditions should be
considered in the validation test suite. If the ICH8 case temperature is above the published Tc-max
in any test scenario, a heatsink is required.
If you determine that the ICH8 package requires a heatsink in your system configuration, please
refer to Appendix A for the current reference ICH8 heatsink vendor information.
The component should be operated above the minimum case temperature specification listed in
Table 2.
®
Table 2. Intel
ICH8 Component Case Temperature Specifications
T
C-MAX
Storage Temperature
NOTES:
1.
10
Parameter
(Note 1 below) for TDP condition
of 4.1 W
T
C-MIN
Without a heatsink, most of the heat dissipated by ICH8 goes through the PCB, acting as a heat
spreader, and then into the ambient air. When a heatsink is installed on the package, more power is
now being pulled through the case. As a result the maximum case temperature must be maintained at
lower level than without a heatsink to remain within specification.
Value
See Table 3 for additional configurations
No Heatsink Attached: 105 °C
See Table 3 for additional configuration
Heatsink Attached: 92 °C
0 °C
-10 °C to +45 °C
Thermal and Mechanical Design Guidelines
R
Advertisement
Table of Contents
