Dell PowerEdge R900 - Manual (Page 78)

78 Installing System Components
SAS Controller Card
Your system includes a dedicated slot for a SAS controller card. The SAS
controller card provides the SAS storage subsystem for your system’s internal
hard drives. The optional SAS RAID controller card allows you to set up any
internal hard drives in a RAID configuration. Although the cabling for the
two types of cards is different (the SAS controller card has only one connector,
while the SAS RAID controller card has two), both cards install into the
dedicated slot as described below. The SAS RAID controller card is shown in
Figure 3-10.