Lenovo 6434 - Manual (Page 30)

System-board optional-device connectors
The following illustration shows the system board and connectors for
user-installable optional devices.
1 DIMM connector 4 PCI Express x4 (x1) connector
2 PCI 32-bit 33 MHz connectors 5 PCI Express x8 connector
3 PCI-X 64-bit 133 MHz connectors 6 Remote Supervisor Adapter II Slim
Line connector
16 ThinkServer TS100 Types 6431, 6432, 6433, and 6434: User Guide