d. beecroft fremont high school 2009-2010 computer performance & storage devices

D. BeecroftFremont High School2009-2010

Computer Performance& Storage Devices

D. BeecroftFremont High School

2009-2010

Computer Performance


2009-2010

Boot Process

Causing the computer to start executing instructions. These instructions search for the operating system, load it and pass control to it.Purposes

• Runs a diagnostic test to make sure everything is working.

• Loading the operating system, so the computer can carry out basic operations.


2009-2010

6 events of the boot process:

Power up Start boot program Power-on self-test Identify peripheral devices Load operating system Check configuration and

customization


2009-2010

Circuits

The path from one component of a computer to another that data uses to travel.

Circuits run between RAM and the

microprocessor RAM and various

storage devices

Silicon Chip

A silicon chip is a piece of almost pure silicon, usually less than one centimeter square and about half a millimeter thick. A silicon chip contains millions of transistors (devices that control the flow of electric current) and other tiny electronic circuit components, packed and interconnected in layers beneath the surface. There is a grid of thin metallic wires on the surface of the chip, which is used to make electrical connections to other devices.


2009-2010


2009-2010

Megahertz (mHz)

A measurement used to describe the speed of the system clock.

A megahertz is equal to one million electrical cycles (or pulses) per second.


2009-2010

Pentium

Name of the CPU. Pentium is the 5th

generation of the Intel processor. Other generations

were called• 80-88• 286• 386• 486


2009-2010

RAM vs. ROM

RAM “Random Access

Memory” A computer chip or

group of chips containing the temporary, or volatile, memory in which programs and data are stored while being used by a computer.

ROM “Read only memory” Drives can read data

from disks, but cannot store new data on them.

A computer chip on the motherboard of a computer containing permanent, or nonvolatile, memory that stores instructions.


2009-2010

RAM ~ Demonstration

Microsoft Word application, the file that is being edited, and operating system are first loaded into Ram.


2009-2010

Binary Number System A number system with a

base of 2. Only uses two numbers (0 and 1). Bit

• The smallest unit of data a computer can understand and act on.

Byte• A combination of

eight bits (0’s and 1’s).

Also referred to as Base 2 Binary Code.


2009-2010

Memory Measurements

Bit Each 0 or 1

Byte 8 bits (group of 8)

Kilobyte Approximately 1,000 bytes Exactly 1,024 bytes

Megabyte Approximately 1 million bytes Approximately 1,000 kilobytes Exactly 1,048,576 bytes

Gigabyte Approximately 1 billion bytes Approximately 1,000

megabytes Terabyte

Approximately 1 trillion bytes Approximately 1,000 gigabytes


2009-2010

Storage Device

A hardware component that houses a secondary storage medium.


2009-2010

Hard Disk

A secondary storage medium consisting of one or more rigid metal platters (disks) mounted on a metal shaft and sealed in a container, called a disk drive, that contains an access mechanism used to write and read data.


2009-2010

Magnetic Storage Device

A storage device that works by applying electrical charges to iron filings on magnetic storage media, orienting each filing in one direction or another to represent a “0” or a “1.” Data are stored and retrieved, or accessed, either sequentially or directly.


2009-2010

Magnetic Tape Storage

A type of secondary storage for large computer systems that used removable reels of magnetic tape. The tape contains tracks that extend the full length of the tape. Each track contains metallic particles that are magnetized, or not magnetized, to represent 0 and 1 bits.

Digital Audio Tape

A signal recording and playback medium developed by Sony in the mid 1980s. In appearance it is similar to a compact audio cassette. As the name suggests, the recording is digital rather than analog. DAT has the ability to record at higher, equal or lower sampling rates than a CD.


2009-10


2009-2010

Floppy Disk

A secondary storage medium consisting of a thin, circular mylar wafer, sandwiched between two sheets of cleaning tissue inside a rigid plastic case.

Write Protection

Any physical mechanism that prevents modification or erasure of valuable data on a device. Most commercial software, audio and video is sold pre-protected


2009-10


2009-2010

Formatting

The procedure of preparing a disk for use during which the disk surface is arranged into tracks, sectors, and clusters.


2009-2010

Formatting a Disk

Sectors: Pie shaped wedges. Tracks: Concentric tracks arranged on the disk.

When users write data and store programs to the disk, the tracks are encoded with 0 and 1 bits.

Cluster: The part of a track crossed by two or more side-by-side sectors forms a cluster. The smallest addressable unit of disk storage.

FAT: The outside tracks contain a table, called the File Allocation Table (FAT), which keeps track of where programs and files are stored.


2009-2010

Zip Disk Higher-capacity floppy disk provides large

secondary storage capacities. Available in 100MB, 250MB, and 750MB

versions.


2009-2010

Jaz Cartridge

A removable hard disk from Iomega.Available in 1 or 2 gig versions.


2009-2010

Optical Disk A secondary storage medium on

which data is recorded and read by two lasers. An optical disk can store several gigabytes of data.High density laser

• Records data by burning tiny indentations, or pits, onto the disk surface.

Low density laser• Reads stored data from the disk into the

computer.


2009-2010

CD-ROM

“Compact Disk – Read Only Memory”

A disk technology in which data is permanently recorded on an optical disk and can be read many times, but the data cannot be changed.


2009-2010

CD-R

“Compact Disk-Recordable” A disk technology that allows a user to

write data onto a compact disk. The disk can be written on only once, cannot be erased, but can be read from an unlimited number of times.


2009-2010

CD-RW

“Compact Disk-Rewritable” A newer type of optical disk storage technology that

uses an erasable disk on which a user can write multiple times.


2009-2010

DVD-ROM

“Digital Video Disk – Read Only Memory”

An extremely high capacity disk capable of holding several gigabytes of data, such as a movie.


2009-2010

Resources

Fuller, Floyd. Computers: Navigating Change. EMC Paradigm, 2002.

Parsons, June Jamrich, and Dan Oja. Computer Concepts. Boston: Course Technology - Thompson Learning, 2002.

Shelly, Gary B.; Cashman, Thomas J.; Vermaat, Misty E. Discovering Computers 2003. Boston: Course Technology – Thompson Learning, 2002.

http://cil.usu.edu/comptech/OSTutorial/

d. beecroft fremont high school 2009-2010 computer performance & storage devices

Documents