Figure 121. Cable routing for 8 x 2.5-inch front SAS/SATA drive bays with an 8i or 16i SFF RAID adapter (Gen 3 or Gen 4)
Table 21.  Mapping between one front SAS/SATA backplane and an SFF HBA/RAID adapter
Backplane From To
Front BP (SAS)
1  SAS 0, SAS 1 1  C0
Cable routing with a CFF RAID adapter
The following illustration and table show the mapping relationship between backplane connectors and a 16i 
CFF RAID adapter (Gen 3 or Gen 4).
170 ThinkSystem SR645 V3 User Guide