Learnings of the week.

Learnings of the Week

by: Mary Trishia V. Tabigue

3 FUNDAMENTAL ELEMENTS OF A COMPUTER

•System Unit
•Output Devices
•Input Devices

•The system unit acts like the center or core, processing the data and information it receives from input devices.
•Output devices like printers receive the system unit’s processed information

The System case

•The system case is a plastic and metal box that houses components such as the motherboard, disk drives and power supply unit.

System Case Types

•There are two basic types of system case: desktop and tower.
•Desktop case: is designed to sit horizontally on a surface, so that it is wider than it is long. These are usually used for office or home PCs. 2 basic sizes: standard and slimline.

•Tower case: is designed to sit vertically on a surface, so that it is higher than it is wide. 3 basic sizes: full, midi and mini.

•Full-tower cases: are usually used for PC servers.
•Midi-tower cases: are used for higher-end user PCs.
•Mini-tower cases: are usually for office or home PCs.

Parts of the Case

•Cover: the case has a cover which is removed by either undoing the screws at the back, or pressing together clips that release it.
•Front Panel: provides access to the floppy and CD, a power on/off switch, a reset switch, and LEDs (light Emitting Diodes) to indicate drive operation.
Parts of front panel cover: CD-R and CD-RW drives, removable hard disk, 3.5 floppy disk,3.5 drive bays, LEDs, Reset switch, Power on/off switch.

THE MOTHERBOARD

•The motherboard is the largest board of the computer system.
•The motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive.
•Chipset: chips that reside on the motherboard.

•The mother board battery: is used to preserve the computer’s clock’s time and your BIOS settings while the computer is turned off.

THE CENTRAL PROCESSING UNIT-CPU

•Is the device that interprets and executes instructions.
•Today’s single-chip central processing units, called microprocessors, make personal computers and workstations possible.
•It has the ability to fetch, decode, and execute instructions and transfer information to and from other resources over the computer’s main data-transfer path, the bus.
•It functions as the brain of a computer

CLOCK

•The system clock synchronizes the operation of all parts of the PC.
•It consists of a clock generator that sets up a timing signal, and clock multipliers.

MEMORY

•2 fundamental types:
–main memory and
–secondary memory

MAIN MEMORY

•Very closely connected to the processor.
•The contents are quickly and easily changed.
•Holds the programs and data that the processor is actively working with.
•Interacts with the processor millions of times per second.

•Most computers available today have memory capacities of 64Mb to 256Mb.
•When programs and data become active, they are copied from secondary memory into main memory where the processor can interact with them.
•Main memory sometimes called: RAM
•RAM (Random Access Memory), radom means that the memory cells can be accessed in any order.

RANDOM ACCESS MEMORY (RAM)

•It means the computer can store, retrieve, alter or delete any items held in the RAM’s at random.
•It is a semiconductor-based memory that can read and written.
•Main memory is build from small circuit boards called MEMORY MODULES.

•Still the current standard in system memory, usually of SDRAM (synchronous RAM) type.
•DIMM chips are usually distributed in 64MB, 128MB or 256 MB on a single chip.
•DIMMs (dual inline memory module) have two access pathways, they do not need to be fitted in pairs as they can be written to and read at the same time

ROM BIOS

•The BIOS (basic input output system) is a ROM (read only memory) chips that provides:
–The industry standard program code that operates the fundamental components of the PC (for example, VDU, keyboard, printer port) and ensures that the design of each manufacturer’s motherboard is PC-compatible.
–The routines that allow the setup configuration of a PC (stored in the CMOS RAM) to be viewed and edited.
–The power-on self-test (POST) diagnostic tests for the PC

•BIOS chip cannot be swapped between different motherboards.
•The BIOS is often known as firmware as it consists of both the physical chip (hardware) and the programs coded into it (software).
•The ROM BIOS is normally a DIP chip that can be identified by a label on the chip.

CMOS RAM

•CMOS RAM stores the configuration of the PC.
•CMOS stands for Complimentary Metal-Oxide Semiconductors, which describes the manufacturing process used to make RAM chip.
•The CMOS battery is either a NICard, lithium or alkaline cell

SECONDARY MEMORY

•Connected to main memory through the bus and a controller
•The contents are easily changed, but this is very slow compared to main memory
•Used for long-term storage of programs and data
•The processor only occasionally interacts with secondary memory

•Common secondary storage devices are the floppy disk and hard disks and compact disks or CD
•It is a thin and flimsy as a sheet of paper but is protected by the sturdy, square jacket that encases it.
•Since the rust is made of iron, which can be magnetized, the disks stores magnetic signals.
•The pattern of magnetic signals is a code representing your data

•3 Standard sizes:
–8-inch is called a largefloppy
–5.25-inch is called a minifloppy
–3.5-inch is called a microfloppy

•5.25-inch floppies were invented by Shugart Associates
•3.35-inch floppies were invented by Sony.
•The typical 3.5 floppy drive holds 1.44 MB.

Drive

•Zip, the most popular super-capacity floppy disks is the Zip disk.
•It holds 100M, which is 70 times as much as 1.44M floppy

HARD DISK

•Might have a storage capacity of 40 gigabytes. This is about 300 times the amount of storage in main memory (assuming 128 megabytes of main memory)
•Hard Drives are usually designated as Drive C

•Hard disks are better than floppy disks in three ways:
–Hard disks are sturdier than floppies
–Hard disks are hard and firm; they don’t flop or jiggle. They’re more reliable than floppies
–Hard drives hold more info. Than floppy drives.

•The typical hard drive holds 40 gigabytes.
•The typical floppy disk rotates between 5 and 10 times per second.
•The typical floppy disk rotates between 5-10 times/second. The typical hard disk rotates between 90-167 times/second.
•The hard disk is non-removable

CD-ROMs

•CD that holds music is called a music CD
•A CD that holds computer data instead is called a computer CD
•The standard CD-ROM disks has a diameter of 12 centimeters and holds 650 megabytes.
•The CD can hold 99 tracks, totaling an hour of music or 650 Mb.

CD-RW

•CD-rewritable drive, which can write onto a blank CD-RW disk and then edit what you wrote.

DVD

•1997, the electronic industry selling an improved kind of CD, called a Digital Versatile Disk (DVD)
•Holds 2-hour movie (including the video and sound)
•Movie Lovers call it a Digital Video Disk

VIDEO CARD

•A board that pugs into a personal computer to give it display capabilities
•Graphics Accelerator: adapters graphics coprocessor for performing graphics calculations
•Video Card are also called video adapter, video board , video display board, graphics card and graphics

UNDERSTANDING VIDEO GRAPHICS

•The video/graphics card converts digital data into signals that can be sent across a connector to you monitor, which interprets the signal into an image on screen.