Thunder i7520 / Thunder i75 20 R Appendix I: Glossary
http://www. tyan.com
46
Appendix I: Glossary
ACPI (Advanced Configuration and Power Interface):
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.
ATAPI (AT Attachment Packet Interface):
also known as IDE or ATA; 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 HDDs.
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 (BIOS Boot Specification):
is a feature within the BIOS that creates, prioritizes, and
maintains a list of all Initial Program Load (IPL) devices, and then stores that list in NVRAM.
IPL devices have the ability to load and execute an OS, as well as provide the ability to return
to the BIOS if the OS load process fails for some reason. At that point, the next IPL device is
called upon to attempt loading of the OS.
BIOS (Basic Input/Output System):
the program that 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 portion of RAM which 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 also the possibility of losing your data should the system crash.
Information stored in a buffer is temporarily stored, not permanently saved.
Bus:
a data pathway. The term is used especially to refer to the connect ion between the
processor and system memory, and between the processor and PCI or ISA local buses.
Bus mastering:
allows peripheral devices and IDEs to access the system memory without
going through the CPU (similar to DMA channels).
Cache:
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 slow 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 4GB 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 which 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 512KB 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.
Closed and open jumpers:
jumpers and jumper pins are active when they are “on” or
“closed”, and inactive when they are “off” or “open”.
