HP Compaq dx7300 MT Hardware Reference Manual page 29

b. If you are removing a standard PCI card, hold the card at each end, and carefully rock it back
and forth until the connectors pull free from the socket. Pull the expansion card straight up
from the socket (1) then away from the inside of the chassis (2) to release it from the chassis
frame. Be sure not to scrape the card against the other components.
Figure 2-11
c. If you are removing a PCI Express x16 card, pull the retention arm on the back of the expansion
socket away from the card and carefully rock the card back and forth until the connectors pull
free from the socket. Pull the expansion card straight up from the socket then away from the
inside of the chassis to release it from the chassis frame. Be sure not to scrape the card against
the other components.
Figure 2-12
ENWW
Removing a Standard PCI Expansion Card
Removing a PCI Express x16 Expansion Card
Removing or Installing an Expansion Card 23