IBM RS/6000 - Manual (Page 47)

2.4.2 Supported Optional Features
In this section, we consider as “optional features” the internal optional devices,
external adapters and external subsystems that can be configured on the RS/6000
Model E20.
2.4.2.1 Internal Disk Drives
Six internal SCSI-2 disk drives can be accommodated in the internal bays of the
system. The disk drives that can be installed and configured are described in
Table 2.
Only disk drives with a 1-inch height (half-height) are supported for internal use.
Disk drives with 1.6-inch height are not supported as they may result in overheating
of the system.
Table 2. Optional Disk Drives on Model E20
Formatted Capacity 1080 MB 1.1 GB 2.2 GB
Feature Number # 2397 # 3032 # 3033
SCSI Bus Rate MB/sec 10 20 20
Average Seek Time ms 12.0 8.5 8.5
RPM 5400 7200 7200
Average Latency ms 5.6 4.17 4.17
Interface SCSI-2 SCSI-2
F/W
SCSI-2
F/W
Data Width 8-bit 16-bit 16-bit
Note: Maximum Internal Disk Drives: 6
2.4.2.2 Internal Tape Drives
Currently, the only tape drive that can be installed in an internal bay of the system
is the 4GB/8GB 4mm Internal Tape Drive.
A maximum of two internal tape drives can be installed. Due to overheating
problems that could lead to data errors, they have to be mounted in bay number 6
and 8, leaving bay number 7 empty. If one tape drive has to be installed, we
suggest mounting it in bay number 8.
Table 3. Optional Tape Drives on Model E20
Tape Capacity 4.0 GB 8.0 GB
Feature Number # 6142 # 6142
Cartridge IBM 4mm DDS IBM 4mm DDS
Data Compression No Yes
Max Effective Transfer Rate 400 KB/sec 800 KB/sec
Interface SCSI-2 (8 bit) SCSI-2 (8 bit)
Bays 1 half-height 1 half-height
Note: Maximum Internal Tape Drives: 2
Chapter 2. PCI-Based RS/6000 Server Hardware 23