Dell Vostro 420 Service Manual page 92

5 For the Vostro 220s:
Replace the chassis support bracket (see "Replacing the Chassis
a
Support Bracket" on page 57).
Replace any hard drives in the hard drive cage (see "Replacing or
b
Adding a Hard Drive" on page 69) that you removed in step 5 of
"Removing the I/O Panel" on page 89.
6 Follow the procedure in "After Working on Your Computer" on page 45.
92
I/O Panel