# IBM ServeRAID-4 hardware features

The following tables list the hardware features for the IBM ServeRAID-4 controllers:

Feature | ServeRAID-4H | ServeRAID-4Mx | ServeRAID-4Lx
--- | --- | --- | ---
Arrays (max.) | 8 | 8 | 8
Battery-backup cache | Yes | Yes | No
Cache memory | 128 MB | 64 MB | 32 MB
Hard disk drives (max.) | 60 | 30 | 15
Logical drives (max.) | 8 | 8 | 8
Microprocessor | 266 MHz | 100 MHz | 100 MHz
SCSI channels | 4 | 2 | 1
SCSI transfer speed (max.) | 160 MB per sec. | 160 MB per sec. | 160 MB per sec.
Supported RAID levels | 0, 1, 5, Enhanced-1 (1E), and Enhanced-5 (5E), 00, 10, 1E0, 50 | 0, 1, 5, Enhanced-1 (1E), and Enhanced-5 (5E), 00, 10, 1E0, 50 | 0, 1, 5, Enhanced-1 (1E), and Enhanced-5 (5E), 00, 10, 1E0, 50
System PCI data bus | 64 bit at 33 MHz | 64 bit at 33 to 66 MHz | 64 bit at 33 to 66 MHz

Feature | ServeRAID-4M | ServeRAID-4L
--- | --- | ---
Arrays (max.) | 8 | 8
Battery-backup cache | Yes | No
Cache memory | 64 MB | 16 MB
Hard disk drives (max.) | 30 | 15
Logical drives (max.) | 8 | 8
Microprocessor | 100 MHz | 100 MHz
SCSI channels | 2 | 1
SCSI transfer speed (max.) | 160 MB per sec. | 160 MB per sec.
Supported RAID levels | 0, 1, 5, Enhanced-1 (1E), and Enhanced-5 (5E), 00, 10, 1E0, 50 | 0, 1, 5, Enhanced-1 (1E), and Enhanced-5 (5E), 00, 10, 1E0, 50
System PCI data bus | 64 bit at 33 MHz | 64 bit at 33 MHz

Glossary | Contents

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