IBM Power System 5105-22E Manual page 70

Figure 53. Disconnecting the signal cable and power cable
6. Ensure that all cables are carefully positioned out of the way, such that the NVMe drive backplane can
be easily lifted and removed.
7. Unscrew the three captive thumbscrews (A) of the NVMe drive backplane (B) as shown in the following
figure until fully loose.
If needed, use a Phillips screwdriver to loosen the screws.
56 Power Systems: Power Systems: Drive backplane