Dell POWEREDGE R805 Hardware Owner's Manual page 171

Figure 6-3. SAS/SATA Backplane Board Components
1
1 drive 0 connector
3 optical drive power (CD_PWR)
5 SAS connector (SAS)
2
front
5
back
2 drive 1 connector
4 backplane power (BKPLN)
Jumpers and Connectors
3
4
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