TYAN S5560, Manual

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IRQ (Interrupt Request): an electronic request that runs from a hardware device to
the CPU. The interrupt controller assigns priorities to incoming requests and delivers
them to the CPU. It is important that there is only one device hooked up to each IRQ
line; doubling up devices on IRQ lines can lock up your system. Plug-n-Play operating
systems can take care of these details for you.
Latency: the amount of time that one part of a system spends waiting for another
part to catch up. This occurs most commonly when the system sends data out to a
peripheral device and has to wait for the peripheral to spread (peripherals tend to be
slower than onboard system components).
NVRAM: ROM and EEPROM are both examples of Non-Volatile RAM, memory that
holds its data without power. DRAM, in contrast, is volatile.
Parallel port: transmits the bits of a byte on eight different wires at the same time.
PCI (Peripheral Component Interconnect): a 32 or 64-bit local bus (data pathway)
which is faster than the ISA bus. Local buses are those which operate within a single
system (as opposed to a network bus, which connects multiple systems).
PCI PIO (PCI Programmable Input/Output) modes: the data transfer modes used
by IDE drives. These modes use the CPU for data transfer (in contrast, DMA channels
do not). PCI refers to the type of bus used by these modes to communicate with the
CPU.
PCI-to-PCI Bridge: allows you to connect multiple PCI devices onto one PCI slot.
Pipeline burst SRAM: a fast secondary cache. It is used as a secondary cache
because SRAM is slower than SDRAM, but usually larger. Data is cached first to the
faster primary cache, and then, when the primary cache is full, to the slower
secondary cache.
PnP (Plug-n-Play): a design standard that has become ascendant in the industry.
Plug-n-Play devices require little set-up to use. 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 with 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 and 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