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PCI-to-PCI bridge: allows you to connect multiple PCI devices onto one PCI slot.
Pipeline burst SRAM: a type of RAM 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 to 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 Independent 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.