Acer Altos R720 Series - Manual (Page 96)

3 System upgrade 86
4 Attach the module to the ARMC/3 module connector on the
mainboard and snap the standoff into the matching hole on the
mainboard (B).
5 Install the NIC module.
a Install the three standoffs to the mainboard.
b Attach the module to the NIC module connector on the
mainboard and matching standoff holes.
6 Observe the post-installation instructions described on page 36.