Figure 24. I/O Module Cooling Air Profile - Dell PowerEdge M1000e Technical Manual

through the server modules, through venting holes in the midplane, and is then drawn into the fans
that exhaust the air from the chassis. There are plenums both upstream of the midplane, between
the midplane and the blades, and downstream of the midplane, between the midplane and the fans,
to more evenly distribute the cooling potential from the three columns of fans across the server
modules.

Figure 24. I/O module cooling air profile

The I/O modules use a bypass duct to draw ambient air from the front of the system to the I/O
module inlet, as seen in Figure 24. This duct is located above the server modules. This cool air is
then drawn down through the I/O modules in a top to bottom flow path and into the plenum
between the midplane and fans, from where it is exhausted from the system.
The power supplies, located in the back of the system, use basic front-to-back cooling, but draw
their inlet air from a duct located beneath the server modules, as seen in Figure 25. This ensures that
the power supplies receive ambient temperature air.
PowerEdge M1000e Technical Guide
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