16 x NVMe front drive bays
This section provides cable routing information for the server model with 16 x 2.5-inch NVMe front drive 
bays.
Onboard connectors + retimer card
The following shows the cable connections for the 16 x 2.5-inch NVMe configuration with onboard 
connectors and one retimer card.
From To
Backplane 1: NVMe 0-1, 2-3 Onboard: PCIe 1, PCIe 2
Backplane 1: NVMe 4-5, 6-7 Retimer card on PCIe slot 1: C0, C1
Backplane 2: NVMe 0-1, 2-3 Onboard: PCIe 3, PCIe 4
Backplane 2: NVMe 4-5, 6-7 Onboard: PCIe 5, PCIe 6
Connections between connectors:  1  ↔  1 ,  2  ↔  2 ,  3  ↔  3 , ...  n  ↔  n
Figure 55. Cable routing for 16 x 2.5-inch NVMe configuration with one retimer card
112 ThinkSystem SR650 V2Maintenance Manual