IBM Power System 5105-22E Manual page 72

Figure 55. Replacing the NVMe drive backplane
3. Carefully tighten each of the three captive thumbscrews (C) to secure the NVMe drive backplane to the
system's chassis, as shown in Figure 55 on page 58.
4. Using your labels, reconnect the signal cable (A) and the power cable (B) to the NVMe drive backplane
as shown in the following figure.
Push the connectors in until the latch clicks.
58 Power Systems: Power Systems: Drive backplane