Fastener with gear usage for tray install and eject

An example computing system includes an I/O module that is securable to the computer chassis. The I/O module includes a gear rack. In additional implementations, the computing system includes a fastening assembly which has a fastener configured to receive an external rotational force from a user. In other implementations, the fastening assembly includes a thread mechanism having first and second portions. The first portion of the thread mechanism are rotatably fixed to the fastener. In other implementations, the fastening assembly includes a gear rotatably fixed to the second portion of the thread mechanism, the gear being configured to engage a gear rack coupled to the I/O module. Upon receiving the external rotational force, the thread mechanism also causes (a) the gear to rotate and (b), in turn, linear movement of the gear rack to (c) secure or unsecure the I/O module relative to the computer chassis.