Asus P2B-D2 - Manual (Page 33)

ASUS P2B-D2 User’s Manual 33
III. INSTALLATION
Connectors
III. INST
ALLA
TION
22. 50-pin Narrow/68-pin Wide/68-pin Ultra2 SCSI Connectors
This motherboard has onboard 50-Pin Narrow SCSI connector for 8-bit SCSI
devices, 68-Pin Wide SCSI connector for 16-bit SCSI devices, and 68-Pin Ul-
tra2 SCSI connector for 16-bit differential SCSI devices.
P2B-D2 Onboard SCSI Connectors
50-pin Narrow
SCSI Connector
68-pin Ultra2
SCSI Connector
68-pin Wide
SCSI Connector
1 35
34 68
1 35
34 68
NOTE: A maximum of 15 devices can be connected using any combination of 50-
pin Narrow SCSI, 68-pin Wide SCSI, and 68-pin Ultra2 SCSI devices.
The onboard Adaptec AIC-7890AB chipset incorporates an advanced multimode I/
O cell that supports both single-ended (SE) and Ultra2 devices. With Ultra2 devices,
the SCSI bus platform performs at full Ultra2 speeds (up to 40 MB/sec in 8-bit mode
and up to 80 MB/sec in 16-bit mode) and extended cabling 12m (or 25m in a point-
to-point configuration). When an SE device is attached, the bus defaults to an SE
speed and cable length.
In mixed environments of Ultra2 and SE devices, the onboard host adapter can be
coupled with the Adaptec AIC-3860 transceiver chipset to bridge the compatibility
gap. By dividing the SCSI bus into independent SE and low voltage differential
(LVD) segments, the transceiver chipset supports legacy devices without limiting
performance and cable length on the LVD segment.
IMPORTANT: Connect SCSI devices as shown. Mixing SCSI devices will lower
performance.
P2B-D2 SCSI Connection
Disk 2 Disk 3 Disk 1
Disk 2 Disk 3 Disk 1
68-pin Ultra2
Scanner Tape CD-ROM
(Terminated)
(Terminated)
50-pin Narrow
68-pin Wide
Terminator
NOTE: Ultra2 devices do not have termination jumpers and must use a separate
terminator on the last connector.