Dell Precision Rack 7910 Owner's Manual page 57

NOTE: To remove expansion-card risers 2 and 3, hold the edges of the expansion-card riser.
NOTE: To ensure proper system cooling, the riser 1 blank must be installed in the riser 1 slot.
Remove the riser 1 blank only if you are installing riser 1.
Figure 23. Removing and installing the expansion card riser 1
1. expansion-card riser 1 cage
3. riser guide-back (right)
5. expansion-card riser 1 connector
2. expansion-card riser 1
4. riser guide-back (left)
6. riser guide-front
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