4 Serial A Connector: A serial signal cable for a modem or other serial deviceconnects to this 9-pin serial connector. Serial port A can be shared by theAdvanced System Management Processor and the operating system. See“Devices and I/O Ports” on page 22 for port assignment information. If youare using a 25-pin signal cable, you need a 9-pin-to-25-pin adapter cable.5 Serial B Connector: A serial signal cable for a modem or other serial deviceconnects to this 9-pin serial connector. Serial port B is used by the operatingsystem and cannot be shared by the Advanced System ManagementProcessor. See “Devices and I/O Ports” on page 22 for port assignmentinformation. If you are using a 25-pin signal cable, you need a 9-pin-to-25-pinadapter cable.6 Hot-Plug PCI Expansion Slots: Your server has three hot-plug PCIexpansion slots.7 Attention Lights for Hot-Plug PCI Slots: Each hot-plug PCI slot has anAttention light that is visible from the rear of the server. An Attention lightflashes approximately once per second when it is on. The meaning of theAttention lights is defined by your operating system. Refer to your operatingsystem documentation to determine if it supports hot-plug PCI adapters and, ifso, what the Attention lights indicate.8 Non-Hot-Plug PCI Expansion Slots: Your server has two non-hot-plug PCIexpansion slots.9 Parallel Connector: A signal cable for a parallel device, such as a printer,connects here.1 SCSI Connector: External SCSI devices attach here. For more information,see “Connecting external options” on page 90.11 Management Port C Connector: This connector is used to attach a modemthat is dedicated to communication with the Advanced System ManagementProcessor.12 Video Connector: The monitor signal cable connects here.13 Universal Serial Bus 1 and 2 Connectors: You can attach an I/O device toeither of these Universal Serial Bus (USB) connectors. USB 2 is theconnector nearest to the edge of the server. You need a 4-pin cable toconnect a device to USB 1 or 2.Note: If a standard (non-USB) keyboard is attached to the keyboard port, theUSB ports are disabled while the power-on self-test (POST) isrunning, and no USB devices will work during POST.14 Ethernet Connector: Your server has one RJ-45 Ethernet connector. Thisconnector is for attaching the network cable to the integrated 10BASE-T or100BASE-TX, twisted-pair transceiver.15 Mouse Connector: The mouse cable connects here. This port sometimes iscalled an auxiliary-device or pointing-device port.16 Keyboard Connector: The keyboard cable connects here.17 Power Connectors: The power cords for the power supplies connect here.Note: For pin assignments and other details about these connectors, see“Connecting external options” on page 90.12 IBM xSeries User's Reference