IBM CS821 Service Manual page 49

b. Remove the two screws that secure the PCIe riser card to the chassis as shown in Figure 33.
c. Lift the PCIe adapter riser at points (A) and (B) from the system backplane.
Figure 33. Removing the PCIe riser screws
5. If the PCIe adapter to remove is in positions 3, 4, or 5, you must remove the PCIe cage and riser.
a. Remove the PCIe riser as shown in Figure 34 on page 34.
1) Retract the retaining pins (A) so that the arrows on the tabs point to the system.
2) Lift the PCIe riser from the system.
Removing and replacing parts
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