Lenovo 3797 - Manual (Page 45)

A 12-drive-capable model server or a diskless model server contains the following
riser card:
1 USB connector
2 PCI Express RAID adapter
3 SAS error LED
A tape-enabled model server contains the following riser card:
1 USB connector
2 PCI Express RAID adapter
3 SATA tape signal
4 Tape power
5 SAS error LED
6 USB tape
PCI riser-card adapter connectors
The following illustration shows the connectors on the PCI riser card for
user-installable PCI adapters.
Chapter 4. Server controls, LEDs, and power 29