Product guide

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Appendix C Glossary
Scalability: The ability to expand. Implies minimal change in
current procedures in order to accommodate growth. When using
“Cluster-aware” application software allows any Application
Programming Interface to do dynamic load balancing and scale
across multiple servers within a cluster.
SCSI: Small Computer System Interface. A processor-
independent standard for system-level interfacing between a
computer and intelligent devices, such as hard disks, floppy
disks, CD-ROM, printers, scanners, and others. SCSI can
connect up to seven devices to a single controller (or “host
adapter”) on the computer’s bus.
SDRAM: Synchronous Dynamic Random Access Memory. This
is a form of DRAM which adds a separate clock signal to the
control signals. These chips can contain more complex state
machines, allowing them to support “burst” access modes that
clock out a series of successive bits.
Setup Program: Used to inform the computer about installed
peripheral, memory, configuration information, date and time, etc.
Shadow RAM: A method of copying BIOS routines from slower
ROM chips to much faster RAM, increasing system performance.
SPD: Serial Presence Detect. A region of non-volatile memory on
the memory module that holds configuration information about the
module.
SRAM: Static Random Access Memory. Does not require periodic
refreshing that dynamic memory requires.
Striping: A process that combines multiple areas of disk space
into one large logical drive. Data is distributed evenly over drives
in a stripe set. All drives in a stripe set work to perform the same
functions done by a single drive in a normal configuration. Allows
concurrent I/O. Striping requires at least two drives. A process
of spreading data evenly over multiple-disk drives to enhance
performance. Data striping can be performed on a bit, byte or
block basis for optimum application performance. Refer to
RAID.
SVGA: Super Video Graphics Array. A set of graphic standards
designed to offer greater resolution than VGA. There are several
varieties of SVGA, each providing a different resolution: 800 x
600 pixels, 1024 x 768 pixels, 1280 x 1024 pixels, 1600 x 1200
pixels. SVGA standards can support up to a palette of 16
million colors, but the number of colors that can be displayed is
limited by the amount of video memory installed in a system.
The base resolution for this standard is 640x480 pixels, with a
color pallet of 256 colors.
System Board: The large printed-circuit board in a computer on
which most electronic devices are mounted; the primary board
in a computer. All other interfaces receive control signals or
information from the system board. Also commonly referred to
as the “mainboard” or “motherboard.”
System: The assembly of basic components (i.e., power
supply, motherboard, memory, video monitor, etc.) united by
some form of communication to form an organized whole.
System Unit: The description for the computer case and all
internal components (i.e., the system board, expansion cards,
disk drives, power supply, etc.).
Tera: Trillion. Abbreviated “T.” Computer specifications refer to
the precise value 1,099,511,627,776.
Terabyte: One trillion bytes. Also, TB, Tbyte and T-byte.