24. Computer Basics
24
âą ROM (read-only memory) is
nonvolatile memory
âHolds program instructions after
power off
âInstruction set for startup
âBIOS (basic input/output system)
25. Computer Basics
25
âą CMOS (complementary metal
oxide semiconductor)
âpermanent as long as battery voltage
is applied
âHolds PC setup
âUser intervention
26. Computer Basics
26
Still other ICs are PGA (pin-grid array) a
square chip package used for the main
processing circuitry.
31. Computer Basics
31
âąISA (industry standard architecture).
â ISA slots are an older technology, used
today for some modems and other relatively
slow devices. Many new computers have few
or no ISA slots
33. Computer Basics
33
âąPCI (peripheral component interconnect).
â PCI slots offer fast transfer speeds and a 64-bit
data bus. These slots typically house a graphics
card, sound card, video capture card, modem, or
network interface card (NIC).
35. Computer Basics
35
âąAGP (accelerated graphics port).
â Primarily used for graphics cards, and faster
than a PCI slot, an AGP slot provides a high-
speed data pathway that is particularly handy
for 3-D graphics.
46. Computer Basics
46
CONNECTORS
Connects to parallel port,
which sends data
simultaneously over
eight data lines at
speeds of 12,000 Kbps
(kilobits per seconds)
LPT
Printer,
external
CD-ROM
drive,
external
Zip,
external
hard drive.
25 pins
49. Computer Basics
49
CONNECTORS
Scuzzy
Connects to SCSI port, which sends
data simultaneously over 8 or 16 data
lines at speeds between 5 Mbps and
80 Mbps (Mega bits per second).
Can support
up to 16
devices in a
âDaisy
Chainâ. Hard
drives,
scanner, CD-
ROM, tape
backup.
50 pins
52. Computer Basics
52
âą Magnetic media
âFloppy disks
âą 3.5â
âą 5.25â
âHard disk
âZip Disk
âTape
â used for backup
Memory storage at present fall into three basic
categories.
53. Computer Basics
53
âą Optical storage media
âCD-ROM
âą compact disk - read only memory
âDVD
âą digital video disc or digital versatile disc
Memory storage at present fall into three basic
categories.