Acer Altos R720 Series User Manual page 53

To install the CPU air duct:
1 Observe the ESD precautions and pre-installation instructions
described on page 35.
2 Place the CPU air duct over the two processor sockets. The front
edge of the air duct should touch the front fan module and the
top of the installed air duct should be flush with the top of the
power supply.
Caution! Do not pinch or unplug cables that may be near or
under the air duct.
3 Observe the post-installation instructions described on page 36.
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