TYAN THUNDER I7522 Manual page 52

Thunder i7520 / Thunder i75 20 R Appendix I: Glossary
PCI -to-PCI bridge: allows you to connect multiple PCI devices onto one PCI slot.
Pipeline burst SRAM: a type of R AM that can maintain it's data as long as power is provided
to the memory chips. In this configuration, SRAM requests are pipelined, which means that
larger packets of data are sent to the memory at one time, and acted upon quickly. This type
of SRAM operates at bus speeds higher than 66MHz.
Pipelining: improves system performance by allowing the CPU to begin executing a second
instruction before the first is completed. A pipeline can be likened to an assembly line, with a
given part of the pipeline repeatedly executing a set part of an operation on a series of
instructions.
PM timers (Power Management timers): software timers that count down the number of
seconds or minutes until the system times out and enters sleep, suspend, or doze mode.
PnP (Plug-n-Play): a design standard that has become ascendant in the industry. Plug- n-Play
devices require little set -up to use. Novice end users can simply plug them into a computer
that is running on a Plug- n-Play aware operating system (such as Windows 98), and go t o
work. Devices and operating systems that are not Plug- n-Play require you to reconfigure your
system each time you add or change any part of your hardware.
PXE (Preboot Execution Environment): one of four components that together make up the
Wired for Management 2.0 baseline specification. PXE was designed to define a standard set
of preboot protocol services within a client, towards the goal of allowing networked -based
booting to boot using industry standard protocols.
RAID (Redundant Array of Indepen dent Disks): a way for the same data to be stored in
different places on many hard drives. By using this method, the data is stored redundantly,
also the multiple hard drives will appear as a single drive to the operating system. RAID level 0
is known as striping, where data is striped (or overlapped) across multiple hard drives, but
offers no fault -tolerance. RAID level 1 is known as mirroring, which stores the data within at
least two hard drives, but does not stripe. RAID level 1 also allows for faster access time and
fault -tolerance, since either hard drive can be read at the same time. RAID level 0+1 is both
striping and mirroring, providing fault -tolerance, striping, and faster access all at the same
time.
RAIDIOS: stands for RAID I/O Steering, a type of RAID technology from Intel. RAIDIOS is a
specification used to enable an embedded I/O controller, embedded on the motherboard, to be
used as just an I/O controller or to be the I/O component of a hardware RAID subsystem. The
RAIDIOS circuit allows an I /O Processor (either embedded on the motherboard or on an add -
in card) to configure the I/O controller and service the I/O controller's interrupts. The I/O
controller and the I/O Processor together are two of the primary components of a hardware
RAID subsystem.
RAM (Random Access Memory): technically refers to a type of memory where any byte can
be accessed without touching the adjacent data, is often used to refer to the system's main
memory. This memory is available to any program running on the computer.
ROM (Read -Only Memory): a storage chip which contains the BIOS; the basic instructions
required to boot the computer and start up the operating system.
S A T A (Serial ATA): is an evolutionary replacement for the Parallel ATA physical storage
interface. Serial ATA is a drop -in solution in that it is compatible with today ' s software and
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