TYAN TOMAHAWK BX Manual page 77

and cooling fan. The keyboard, mouse, serial, USB, and parallel ports are built
in.
Bandwidth
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.
BBS
A (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.
BIOS
The (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.
buffer
A is a portion of RAM which is used to temporarily store data, usually
from an application, though it is also used when printing, and in most key-
board 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. Informa-
tion stored in a buffer is temporarily stored, not permanently saved.
bus
A is a data pathway. The term is used especially to refer to the connec-
tion between the processor and system memory, and between the processor
and PCI or ISA local buses.
Bus mastering
memory without going through the CPU (similar to DMA channels).
cache
A is a temporary storage area for data that will be needed often by an
application. Using a cache lowers data access times, since 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 1GB of regular memory.
Cache 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
S1856 Tomahawk BX/A+
allows peripheral devices and IDEs to access the system
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