Dell Vostro 420 Service Manual page 79

9 For the Vostro 220s, push the release latch down to secure the optical drive
and the 3.5-inch device in their respective drive cages.
NOTE:
Install the media card reader into the drive bay before you connect the USB
interface cable to the back of the device.
10 Connect the USB interface cable to the back of the device.
NOTICE:
The connectors are "keyed" for correct insertion; that is, a notch or a
missing pin on one connector fits with a tab or a filled-in hole on the other
connector. Align the cable connectors correctly before inserting them to avoid
damage to the connectors.
11 Ensure that the other end of the USB interface cable is connected to a
USB connector on the system board (see "System Board Components" on
page 40).
1
1 screws (2)
3 media card reader
12 Replace the bezel (see "Replacing the Bezel" on page 53).
4
3
2 screw holes (2)
4 USB interface cable
2
Drives
79