Cooling Sub-System - Intel SR1500 - AXXMINIDIMM DDR-2 RAID Controller Cache Memory Manual

2BCooling Sub-System Intel® Server System SR2500AL
3.

Cooling Sub-System

Several components and configuration requirements make up the cooling sub-system of the
chassis. These include the system fan module, the power supply fans, air baffles, CPU air duct,
and drive bay population. All are necessary to provide and regulate the air flow and air pressure
needed to maintain the system's thermals when operating at or below maximum specified
thermal limits. See Table 54. System Environmental Limits.
Two system fan assembly options are available for this chassis. The first option is a non-
redundant three fan solution providing sufficient airflow to maintain internal system thermal
requirements when the external ambient temperature remains within specified limits. The
second option is a redundant fan solution. Three parallel sets of fans are arranged in series to
provide redundant cooling in the event of a single fan failure. Each cooling option utilizes two
fan types: a 60mm variable speed fan and an 80mm variable speed fan.
The chassis uses a variable fan speed control engine to provide adequate cooling for the
system at various ambient temperature conditions, under various server workloads, and with the
least amount of acoustic noise possible. The fans operate at the lowest speed for any given
condition in order to minimize acoustics. The Baseboard Management Controller (BMC)
®
integrated on the Intel
Server Board S5000PAL is used for the variable fan speed control
function. The controller monitors selective component temperatures and the ambient
temperature, as well as each fan's RPM to determine the necessary airflow. The BMC sets the
fan speeds to the appropriate RPM in order to maintain proper cooling. The BMC controller will
also log errors into the System Event Log (SEL) when temperature sensors exceed their safe
operating ranges, or if any of the fans fail to operate at safe airflow speeds. In the event of a
fan failure, the BMC will boost the remaining fans to compensate for the lost air flow. A chassis
with redundant fans can continue to operate in this degraded condition while the non-redundant
chassis may not. If the cooling is not sufficient under a failed fan condition, the system will
eventually shutdown to protect itself from thermal damage.
20 Revision – 1.6
Intel order number D31980-009