HP EliteDesk 705 G1 Microtower Hardware Reference Manual page 20

Removing or installing an expansion card
The computer has two PCI Express x1 expansion slots, one PCI Express x16 expansion slot, and
one PCI Express x16 expansion slot that is downshifted to a x4 slot.
NOTE: You can install a PCI Express x1, x8, or x16 expansion card in the PCI Express x16 slot.
For dual graphics card configurations, the first (primary) card must be installed in the PCI Express
x16 slot that is NOT downshifted to a x4.
To remove, replace, or add an expansion card:
1. Remove/disengage any security devices that prohibit opening the computer.
2. Remove all removable media, such as compact discs or USB flash drives, from the computer.
3. Turn off the computer properly through the operating system, then turn off any external devices.
4. Disconnect the power cord from the power outlet and disconnect any external devices.
CAUTION:
as long as the system is plugged into an active AC outlet. You must disconnect the power cord
to avoid damage to the internal components of the computer.
5. Remove the computer access panel.
6. Release the slot cover retention latch that secures the slot covers by lifting the tab on the latch
and rotating the latch to the open position.
7. Locate the correct vacant expansion socket on the system board and the corresponding
expansion slot on the back of the computer chassis.
8. Before installing an expansion card, remove the expansion slot cover or the existing expansion
card.
NOTE:
attached to the expansion card.
a. If you are installing an expansion card in a vacant socket, you must slide one of the
expansion slot covers up and out of the chassis or use a flatblade screwdriver to pry out
14 Chapter 2 Hardware upgrades
Regardless of the power-on state, voltage is always present on the system board
Before removing an installed expansion card, disconnect any cables that may be