HP dx2040 - Microtower PC Hardware Reference Manual page 24

7. If you are installing an expansion card for the first time, you must use a flatblade screwdriver to pry
out the metal shield on the rear panel that covers the expansion slot. Be sure to remove the
appropriate shield for the expansion card you are installing.
Figure 2-8
Removable Shield
Top shield
Second shield
Third shield
Bottom shield
18 Chapter 2 Hardware Upgrades
Removing an Expansion Slot Cover
Expansion Card Type
PCI Express x16
PCI Express x1
PCI
PCI
ENWW