HP rp5800 Reference Manual page 28

10. To install a new 12-volt Powered USB expansion card, hold the card just above the PCI Express
expansion socket on the system board then move the card toward the rear of the chassis (1) so
that the bracket on the card is aligned with the open slot on the rear of the chassis. Press the
card straight down into the expansion socket on the system board (2).
NOTE:
the PCI Express x16 slot, or both. Two 12-volt Powered USB expansion cards are supported.
Figure 2-17
NOTE:
connector seats properly in the expansion card slot.
22 Chapter 2 Hardware Upgrades
You can install the Powered USB expansion card in either the PCI Express x1 slot or
Installing a 12-volt Powered USB Expansion Card
When installing an expansion card, press firmly on the card so that the whole
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