Chapter 5. IBM AS/400e 720, 730, and 740 models 185
#2748 #2748 PCI RAID Disk Unit Controller — 26 MB Cache (RAID Mirrored/Unprotected) (Ultra2 SCSI)
The #2748 PCI RAID Disk Unit Controller is Ultra2 SCSI capable when installed in the #5065 Storage/PCI Expansion
Tower is Ultra SCSI capable when installed in the Model 720 system unit or a #5064/#9364 system unit expansion. The
#2748 has a 26 MB write-cache and provides RAID-5 protection and compression for internal disk units. It supports up to
15 disks. A minimum of four drives and a maximum of 10 drives are supported in each array. A maximum of three arrays
is allowed for each #2748. The #2748 supports both compression and non-compression modes. The mode is determined
by a hardware jumper on the card. The #2748 also supports #6831/#4331 1.6 GB Read Cache Device. When placed in
the system unit, it supports one internal tape and one CD-ROM. In the #5064/#9364 system unit expansion, it supports up
to three internal tape and CD-ROM. In the #5065 Storage/PCI Expansion Tower, it supports up to two internal tapes and
CD-ROM.
It supports the #1349, #1350, #1355, #1360, #4482, #4483, #4486, #4684, #6480, #6481, #6482, #6483, #6384, #6485,
#6486, or #6490 tape units. Mutually exclusive of #2726, #2740 PCI RAID Disk Unit Controller, #2741 PCI RAID Disk Unit
Controller, or #9728 in the same system unit or #9330 PCI integrated expansion unit.
High-speed PCI slots required: One
Prerequisite: System unit or #5064/#9364 system unit expansion with #9330 PCI integrated expansion unit or #5065
Storage/PCI Expansion Tower
Maximum: One per system unit or #9364, three per #5065 Storage/PCI Expansion Tower
Minimum operating system level: OS/400 V4R4
#2778 #2778 PCI RAID Disk Unit Controller — 104 MB Cache (RAID Mirrored/Unprotected) (Ultra2 SCSI)
The #2778 PCI RAID Disk Unit Controller is an Ultra2 SCSI controller with a maximum compressed write cache size of
104 MB that provides RAID-5 protection and compression for internal disk units and supports internal tape units and
CD-ROMs. The #2778 supports both disk compression and enhanced modes. The mode of operation is determined by a
hardware jumper and disk compression mode should only be used when disk compression is desired. In addition to
providing RAID-5 protection for disks, the #2778 is also designed to work as a high performance controller for disks
protected by system mirroring or disks with no protection. A minimum of four disk units of the same capacity is needed for
a valid RAID-5 configuration. A maximum of four arrays is allowed per controller, with a maximum of 10 disk units allowed
per array. All disk units in an array must be of the same capacity.
The #2778 supports the #4331 1.6 GB Read Cache Device, which is used by Extended Adaptive Cache to provide
increased performance. The #4331 1.6 GB Read Cache Device is supported only when #2778 is in enhanced mode.
The #2778 controller supports a maximum of 15 disk units and up to two removable media devices (internal tape or
CD-ROM). The #2778 is the only disk unit controller that supports compression on 36 GB disk units.
Prerequisite: An available high-speed SCSI slot in #5065/#5066 PCI Expansion Tower
Maximums: Three (in combination with #2748 PCI RAID Disk Unit Controller) per #5065 Storage/PCI Expansion Tower;
six (in combination with #2748 PCI RAID Disk Unit Controller) per #5066 1.8 M I/O Tower
Minimum operating system level: OS/400 V5R1
The #2778 was withdrawn from marketing on 01 October 2004. The recommended replacement is a #2757 PCI-X Ultra
RAID Disk Controller.
#6112 #6112 Magnetic Storage Device Controller (SPD)
The #6112 provides attachment for up to two 9331-001 or 002 Diskette Units and up to two 9347 Tape Units.
SPD slots required: One
Maximum: Two for 9331, two for 9347; limit of two #6112s in #9331 expansion unit for SPD cards on Model 720
#6146 #6146 Diskette Adapter (SPD)
The #6146 provides attachment for one 9331 011, 012 Diskette Unit, and the #6135 5 ¼-inch diskette.
SPD slots required: None
Prerequisite: #2624 Storage Device Controller
Maximum: Two
#6500 Direct Access Storage Device Controller (SPD)
The #6500 provides attachment for one 9337 0xx or 1xx.
SPD slots required: One
