LSI MegaRAID SCSI 320-2 RAID Controller Series 518 - Manual (Page 53)

MegaRAID Components 4-9
Copyright © 2002 by LSI Logic Corporation. All rights reserved.
transfers, RAID processing, drive rebuilding, cache management, and
error recovery.
4.10.2 Cache Memory
Cache memory resides in a single 72-bit DIMM socket that requires one
unbuffered 3.3 V SDRAM single-sided or double-sided DIMM. Possible
configurations are 32, 64, 128, or 256 Mbytes.
MegaRAID supports write-through or write-back caching, which can be
selected for each logical drive. To improve performance in sequential disk
accesses, MegaRAID does not use read-ahead caching for the current
logical drive. The default setting for the read policy is Normal, meaning
no read-ahead caching. You can disable read-ahead caching.
Warning: Write caching is not recommended for the physical drives.
When write cache is enabled, loss of data can occur when
power is interrupted.
4.10.3 MegaRAID BIOS
The BIOS resides on a 1 MB or 2 MB 8 flash ROM for easy upgrade.
The MegaRAID BIOS supports INT 13h calls to boot DOS without
special software or device drivers. The MegaRAID BIOS provides an
extensive setup utility that can be accessed by pressing <Ctrl> <M> at
BIOS initialization. The MegaRAID Configuration Utility is described in
the MegaRAID Configuration Software Guide.
4.10.4 Onboard Speaker
The MegaRAID SCSI 320-2 has an onboard tone generator for audible
warnings when system errors occur. Audible warnings can be generated
through this speaker. The audible warnings are listed in Appendix B.
4.10.5 Serial Port
The MegaRAID SCSI 320-2 has a 3-pin RS232C-compatible serial port
connector, which is used for test purposes only.