IBM IntelliStation Z Pro 6221, Руководство по техническому обслуживанию аппаратной части

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SCSI cabling requirements
You can install three internal SCSI devices using the SCSI signal cable that comes
with some computer models. If you plan to attach external SCSI devices, you must
order an additional SCSI cable, remove the SCSI knockout from the rear of the
computer, and connect the new cable from the system board to this opening. To
select and order the correct cables for use with external devices, contact your IBM
reseller or IBM marketing representative. When using an optional SCSI adapter, you
must also connect the SCSI adapter to the SCSI LED (J18) connector on the
system board receive an indication of SCSI hard-disk drive activity. See
“System-board internal connectors” on page 37 for the location of the SCSI
connectors.
Setting SCSI IDs
Each SCSI device connected to a SCSI controller must have a unique SCSI ID.
This ID enables the SCSI controller to identify the device and ensure that different
devices on the same SCSI channel do not attempt to transfer data simultaneously.
SCSI devices that are connected to different SCSI channels can have duplicate
SCSI IDs. See the information that is provided with the device for instructions about
setting its SCSI ID.
Universal Serial Bus connectors
There are four Universal Serial Bus (USB) v2.0 connectors, two on the front of the
computer and two on the rear of the computer. Use the USB connectors to connect
optional telephony and multimedia devices. USB 2.0 technology transfers data at up
to 480 megabits per second (Mbps) with a maximum of 127 external devices and a
maximum signal distance of 5 meters (16 ft) per segment (if the device that is
attached to the computer is a USB 2.0 device). If the computer has multiple USB
devices attached to it, the USB hub must be USB 2.0, otherwise, all USB 2.0
devices will transfer data at 12 Mbps. Using Plug and Play technology, USB devices
are configured automatically. The following illustration shows a USB connector.
1 4
Use a 4-pin USB cable to connect external devices to USB connectors.
If you connect a PS/2 (non-USB) keyboard to the keyboard connector, USB ports
and devices are disabled during power-on self-test (POST).
If you connect a USB keyboard that has a mouse port, the keyboard emulates a
mouse, and you cannot disable the mouse settings in the Configuration/Setup Utility
program.
Video connector
The Accelerated Graphics Port (AGP) adapter, which is in the AGP slot on the
system board, provides the video connector. This connector is on the rear of the
computer. Use the video connector to connect a monitor or other display. The
following illustrations show the different types of video connector that can come with
your computer.
Analog video connector :
Installing options
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