NEC Express5800/120Mc2 series, User Manual

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System Cabling A-3
Standard Configuration
Your system is cabled using a single channel on-board IDE Controller and dual channel
on-board Adaptec 7899 SCSI Controller.
The on-board IDE controller supports the standard internally mounted CD-ROM as its
master device. If only one device is on a channel connector it must be set as the master
device.
The AIC 7899 contains two independent SCSI channels that share a single PCI bus
master interface. Each channel is capable of operations using either 8- or 16-bit SCSI
providing 160 MB/s (Ultra-160/M) or 80 MB/s (Wide Ultra2) throughput. As
implemented on the system board controller A attaches to an Ultra-160/M SCSI
backplane that supports up to seven 160/M SCA drives. Controller B can be used to
support SCSI devices in the removable media bays. A 68 pin to 50 pin converter is also
available to be used when installing SCSI narrow devices.
A 3.5-inch diskette drive is also installed in all systems and interfaces separately to the
system board.
Referring to the Figure below, a 68-pin Ultra-160/M SCSI interface cable (K) is
connected to the SCSI connector (J) on the middle right edge of the system board. This
cable connects to the rear of the hard disk drive's SCSI backplane (L).
The IDE interface cable (E) is connected to the IDE connector (D) towards the middle
right edge of the system board. This cable connects to the rear of the internally mounted
CD-ROM drive (F).
Optional internally mounted SCSI removable media devices (I) may be connected to the
SCSI controller connector (G).