NEC POWERMATE 5100 - SERVICE, Руководство по обслуживанию

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14 Glossary
serial printer
A printer with a serial interface.
SGRAM
Synchronous Graphic Random Access Memory. A type of DRAM used
increasingly on video adapters and graphics accelerators. Like SDRAM, SGRAM
can synchronize itself with the CPU bus clock at speeds of up to 100 MHz. In
addition, SGRAM uses several other techniques, such as masked writes and block
writes, to increase bandwidth for graphics-intensive functions. Unlike VRAM and
WRAM, SGRAM is single-ported (it can only be accessed by one device at a time).
However, it can open two memory pages at once, which simulates the dual-port
nature of other video RAM technologies (access by two different devices
simultaneously). See VRAM and WRAM.
SIMM
Single Inline Memory Module. A small circuit board holding a group of memory
chips. Typically, SIMMs hold up to nine RAM chips. On PCs, the ninth chip is for
parity error checking. Unlike memory chips, SIMMs are measured in bytes rather
than bits. In today’s SIMMs, each chip holds 2 MB, so a single SIMM holds 16
MB. SIMMs are easier to install than individual memory chips. The bus from a
SIMM to the actual memory chips is 32 bits wide. A newer technology, called dual
in-line memory module (DIMM), provides a 64-bit bus. To take advantage of the
64-bit bus on Celeron and Pentium II processors, use either DIMMs or pairs of
SIMMs. See DIMMs.
Slot 1
The form factor for Intel Pentium II processors. The Slot 1 package replaces the
Socket 7 and Socket 8 form factors used by previous Pentium processors. Slot 1 is a
242-pin daughter card slot that accepts a microprocessor packaged as a Single Edge
Contact (SEC) cartridge. A system board can have one or two Slot 1s. See SEC.
SMART
Self-Monitoring Analysis and Reporting Technology. A hard drive feature that
works in conjunction with system software (for example, LANDesk Client
Manager, NEC Auto Backup) for identifying a potential problem on the hard drive
and automatically backing up system files to a user-specified device, such as a tape
or Zip drive.
sound card
An expansion card designed for sound input and output. Sound cards can record
and play back digital audio. Most also have a MIDI synthesizer, which means they
can play MIDI files; some also have MIDI inputs and outputs.
super video graphics array (SVGA)
A color bit-mapped graphics display standard that provides a resolution of 1024x
768 with up to 256 colors displayed simultaneously.
synchronous
Refers to protocols that require the clocks of the communicating machines to be
coordinated.