(Advanced Configuration and Power Interface)
is a power management specification that allows the operating system to
control the amount of power distributed to the computer's devices.
Devices not in use can be turned off, reducing unnecessary power
expenditure. ACPI defines a new interface to
the system board, and enables the OnNow design initiative for instantly
(Accelerated Graphics Port) is a PCI-based interface
that was designed specifically for demands of 3D graphics applications.
The 32-bit AGP channel directly links the graphics controller to the main
memory. While the channel runs at only 66 MHz, it supports data
transmission during both the rising and falling ends of the clock cycle,
yielding an effective speed of 133 MHz. [ top]
(AGP In-line Memory Module) - 4 MB Display
Cache card that plugs into the AGP port to gain additional performance.
(Audio Modem Riser) is Intel's specification on
motherboard design. Motherboard with this type of architecture
allows for designs w/o analog I/O functions. However, these
functions can be added by the codec chip on a riser card, which plugs into
the motherboard perpendicularly, resulting in better audio quality.
is two or more hard disk drives grouped together to appear as a single
device to the host computer. [top]
was the original form factor of IBM's PC.
(AT Attachment Packet Interface), also known as IDE
or ATA, is a drive implementation that includes the disk controller on the
device itself. It allows CD-ROMs and tape drives to be configured as
master or slave devices, just like hard drives. [top]
form factor was designed to replace the AT form factor. It improves
on the AT design by rotating the board ninety degrees, so that the IDE
connectors are closer to the drive bays, and the CPU is closer to the
power supply and cooling fan. The keyboard, mouse, serial, USB, and
parallel ports are built in.
refers to carrying capacity. The greater the bandwidth, the more
data the bus, phone line, or other electrical path, can carry.
Greater bandwidth, then, also results in greater speed. [
(Bulletin Board System) is a computer system with a
number of modems hooked up to it which acts as a center for users to post
messages and access information.
(Basic Input/Output System) program resides
in the ROM chip, and provides the basic instructions for controlling your
computer's hardware. Both the operating system and application
software use BIOS routines to ensure compatibility. [top]
Array Support refers to the ability to make the system boot
from a RAID array instead of from a standalone (single) disk.
is a portion of RAM that is used to temporarily store data, usually
from an application, though it is also used when printing, and in most
keyboard drivers. The CPU can manipulate data in a buffer before
copying it, all at once, to a disk drive. While this improves system
performance -- reading to or writing from a disk drive a single time is
much faster than doing so repeatedly -- there is the possibility of losing
your data should the system crash. Information stored in a buffer is
temporarily stored, not permanently saved.
is a data pathway. The term is used especially to refer to the
connection between the processor and system memory, and between the
processor and PCI or ISA local buses. [top]
Mastering allows peripheral devices and IDEs to access the
system memory without going through the CPU (similar to DMA channels).
is a temporary, fast storage area that holds data from a slower storage
device for quick access as needed by an application. Access time is
fast using a cache, because the needed information is stored in the SRAM
instead of in the slower DRAM. Note that the cache is also much
smaller than your regular memory: a typical cache size is 512KB, while you
may have as much as 2GB of regular memory. [ top]
size refers to the physical size of the cache onboard.
This should not be confused with the cacheable area, which is the total
amount of memory that can be scanned by the system in search of data to
put into the cache. A typical setup would be a cache size of 512KB,
and a cacheable area of 512MB. In this case, up to 512MB of the main
memory onboard is capable of being cached. However, only 512KB of
this memory will be in the cache at any given moment. Any main
memory above 512MB could never be cached.
and open jumpers Jumpers and jumper pins are active when
they are On or Closed, and inactive when they are Off or Open. [top]
(Complementary Metal-Oxide Semiconductors) are
chips that hold the basic start-up information for the BIOS.
(Communication & Network Riser)
(Color-decoder) is a filter that manipulates data in some
form, usually by compressing or decompressing the data stream. [top]
port is another name for the serial port, which is so-called
because it transmits the eight bits of a byte of data along one wire, and
receives data on another single wire (that is, the data is transmitted in
serial form, one bit after another). Parallel ports transmit the
bits of a byte on eight different wires at the same time (that is, in
parallel form, eight bits at the same time).
resides on an array that relieves the host CPU from executing
processor-intensive operations such as RAID 5 parity calculations and
secondary RAID 1 writes.
(Display C ache)
(Dual In-line Memory Modules) are a faster and
more capacious form of RAM than SIMMs, and do not need to
be installed in pairs. [top]
banks are sometimes called DIMM sockets, because the physical
slot and the logical unit are the same. That is, one DIMM module
fits into one DIMM socket, which is capable of acting as a memory bank.
Direct Memory Access channels are similar to IRQs.
DMA channels allow hardware devices (like sound cards or keyboards) to
access the main memory without involving the CPU. This frees up CPU
resources for other tasks. As with IRQs, it is vital that you do not
double up devices on a single line. Plug and Play devices will take
care of this for you. [top]
mode , only the CPU's speed is slowed.
(Dynamic RAM) is a widely available, very affordable form of
RAM that has the unfortunate tendency to lose data if it is not recharged
regularly (every few milliseconds). This refresh requirement makes
DRAM slower by a factor of three to ten compares to non-recharged RAM such
as SRAM. [ top]
means mirroring across two RAID cards.
Array Expansion - see "Online Capacity
(Error-Correcting C ode) functions to test the
accuracy of data transmission, both in and out of memory. [top]
DRAM (Extended Data Output DRAM) a
faster type of DRAM in that it can start working on the next block of
memory at the same time it sends previous one to CPU.
(Electrically Erasable Programmable ROM) also
called Flash BIOS, is a ROM chip that can, unlike normal ROM, be updated.
This allows you to keep up with changes in the BIOS programs without
having to buy a new chip. TYAN's BIOS
(Extended System Configuration Data) is a
format for storing information about Plug and Play devices in the system
BIOS. This information helps properly configure the system each time
Tolerance refers to the ability of a system to continue to
perform its functions even when one or more hard disk drives have failed.
is low level software that controls the system hardware.
factor is an industry term for the size, shape, power supply
type, and external connector type of the PCB (personal computer board) or
motherboard. The standard form factors are the AT and ATX, although
TYAN also makes some Baby-AT boards. [ top]
Global timer is an onboard hardware timer, such as the Real
is a form of encryption. One system, typically the server, sends an
encryption scheme to another agent, typically a client. Thus, the
client's data is protected during transmittal to the server. [top]
(Hardware Compatibility Test) is a suite of tests
from WHQL that verifies hardware and device driver operations under a
specific operating environment.
for Hard Disk Drive. [top]
stands for Human Interface Device USB peripheral
Spare - A spare hard drive will automatically be used to
replace the failed member of a redundant disk array.
Swap refers to the ability to remove a failed member of a
redundant disk array and replace it with a good drive without bringing
down the server or interrupting transactions that involve other devices. [
controls the horizontal properties of the monitor.
(Integrated Circuit) is the formal name for the computer
(Integrated Device/Drive Electronics) is a
simple, self-contained hard drive interface. It can handle drives up
to 8.4GB in size. Almost all IDEs sold now are in fact Enhanced IDEs
INT (IDE Interrupt) is a hardware interrupt
signal that goes to the IDE. [top]
(Input / Output) is the connection between your computer and
another piece of hardware (mouse, keyboard, etc.).
(Interrupt Request) is 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. Happily,
Plug and Play operating systems take care of these details for you. [top]
(Industry Standard Architecture) is a slower 8- or
16-bit BUS (data pathway).
(Local-Area Network) connects to workstations, PC's,
or other LANs to enable data access and device sharing. Wake-on-LAN
refers to ability to revive a system from sleep mode over a network
without physically touching the system. [ top]
is the amount of time that one part of a system spends waiting for another
part to catch up. This is most common when the system sends data out
to a peripheral device, and is waiting for the peripheral to send some
data back (peripherals tend to be slower than onboard system components).
- A processor on the RAID card which performs all RAID management
functions (for example, the Intel i960). Microprocessors offer
higher performance compared to co-processors.
(RAID 1) provides data protection by duplicating all data from a primary
drive on a secondary drive. [top]
(Network Operating System), i.e. NetWare, Windows NT
ROM and EEPROM are both examples of Non-Volatile RAM,
memory that holds its data without power. DRAM, in contrast, is
(Original Equipment Manufacturers) refers to
companies such as Compaq or IBM that package other companies' motherboards
and hardware inside their case and sell them.
Capacity Expansion (O.C.E.) - A process for
adding storage capacity to an existing RAID array without having to take
the server offline. Also known as Dynamic Array Expansion.
, a term for a PC that is always on but appears off and that responds
immediately to user or other requests. [top]
port transmits the bits of a byte on eight different wires at
the same time (that is, in parallel form, eight bits at the same time).
is a form of data protection used by RAID level 5 to recreate the data of
a failed drive in a disk array. [top]
is the 1999 - 2000 requirements for PC system and peripheral design for
the "Designed for Microsoft Windows" logo. Such as ACPI
support and NO ISA slots.
(Peripheral Component Interconnect) is a 32-bit
local bus (data pathway) which is faster than ISA bus. Local buses
are those that operate within a single system (as opposed to a network
bus, which connects multiple systems). [top]
PIO (PCI Programmable Input / Output)
modes are the data transfer modes used by IDE drives. These modes
use the CPU for data transfer (DMA channels do not). PCI refers to
the type of bus used by these modes to communicate with the CPU.
bridge allows you to connect multiple PCI devices onto one PCI
burst SRAM is 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.
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.
timers (Power Management timers) are
software timers that count down the number of seconds or minutes until the
system times out and enters sleep, suspend, or doze mode. [top]
is an acronym for Plug and Play, a design standard that has become
ascendant in the industry. Plug and Play devices require little
set-up to use. Novice end users can simply plug them into a computer
that is running on a Plug and Play-aware operating system (such as Windows
95), and go to work. Devices and operating systems that are not Plug
and Play require you to reconfigure your system each time you add or
change any part of your hardware.
(Redundant Array of Independent Disks) is a
method of combining multiple hard drives into one unit. It offers
fault tolerance and higher throughput levels than a single hard drive or a
group of independent hard drives. [ more
on RAID ]
Levels (0 through 5) refer to different array architectures
that offer various advantages in terms of data availability, cost and
performance. RAID levels 0, 1, 0/1, and 5 are the most popular. [
0 - See " Striping".
0/1 - Combines RAID 0 (data striping) and RAID 1 (disk
1 - See " Mirroring". [top
5 - Combines data striping (for enhanced performance) with
distributed parity (for data protection) to provide a recovery path in
case of failure.
Management Software makes installation, configuration, and
management of RAID arrays easy. Often includes features such as
pager notification and remote management.
The term RAM
(Random Access Memory), while technically referring
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. [top]
(Read-Only Memory) is a storage chip which contains
the BIOS (Basic Input / Output System), the basic instructions required to
boot the computer and start up the operating system.
(Small Computer S ystem Interface) is the
technology that allows you to connect various devices to your PC.
This connection is made using a SCSI card that fits inside your computer.
(Synchronous Dynamic RAM) is so-called because it can
keep two sets of memory addresses open simultaneously. By
transferring data alternately from one set of addresses, and then the
other, SDRAM cuts down on the delays associated with non-synchronous RAM,
which must close one address bank before opening the next.
Port is so called because it transmits the eight bits of a byte
of data along one wire, and receives data on another single wire (that is,
the data is transmitted in serial form, one bit after another). [top]
(Single In-line Memory Modules) are the most
common form of RAM. They must be installed in pairs, and do not have
the carrying capacity or the speed of DIMMs.
bank/socket SIMM sockets are the physical slots into which you
stick SIMM modules. A pair of SIMM sockets forms a SIMM bank, and
act as a unit. If only one socket is filled, the bank will not
/ Suspend mode, all devices except the CPU shut down.
(Shared Memory Architecture) with system memory.
- A two-wire interface through which simple system and power
management related chips can communicate with the rest of the system.
It is based on the principals of the operation of I2C.
(System Management Bus) is a two-wire interface based
on the I2C protocol. It is a low-speed bus that provides positive
addressing for devices, as well as bus arbitration. [top]
Static RAM, unlike DRAM, does not need to be refreshed in
order to prevent data loss. Thus, it is faster, and more expensive.
mode , the video and fixed disk drive shut down; all other
devices operate normally.
(RAID 0) - Spreads data evenly over
multiple drives to enhance performance. Because there is no
redundancy scheme, it does not provide data protection.
Computers - Producer of a quality line of systems boards, and
is a fast version of the old DMA channel. UltraDMA is also called
UltraATX. Without UltraDMA your system cannot take advantage of the
higher data transmission rates of the new UltraATA hard drives.
(Universal Serial Bus) is a versatile port. It
can function as a serial, parallel, mouse, keyboard, or joystick port.
It is fast enough, 12Mbps, to support video transfer, and is capable of supporting
up to 127 daisy-chained peripheral devices. [top]
(Universal Serial Bus
High Speed) is the next generation of Universal Serial Bus is
40X faster than USB 1.1 with a transfer rate of 480 Mbps. USB 2.0
will allow all sorts of new and improved USB devices to be added to the
USB product lineup such as fast disk drives, CDRW's, High Quality Video
Cameras, and High High Speed Scanners.
( Virtual Channel Memory) is the new SDRAM
architecture, which realizes flexible and high-efficiency data transfer by
incorporating channel buffers configured by high-speed registers.
(Video Graphics Array) is the PC video display
(Voltage Regulator Module) regulates the voltage fed
to the microprocessor.
controls the vertical properties of the monitor. [top]
( Wired for Management) is an Intel guideline on the
implementation of system management.
(Windows Hardware Quality Libs) is the test
procedure for "Designed for Microsoft Windows" logo. [top]
sockets (Zero Insertion
Force Sockets) make it possible to insert CPUs without
damaging the sensitive pins. The CPU is lightly placed in an open
ZIF socket, and the metal lever pulled down. This shifts the
processor over and down, guiding it into place on the board.