Computer Hardware and Components Most computers are made of many components that can be changed for better ones as time goes by. Here is a list of the common computer hardware components found on the market. AGP Slot : Accelerated Graphic Port. This was introduced to allow the display cards to access the system memory directly without going through a shared PCI bus and allow a faster processing to accommodate the 3D games and other intensive display applications. There is only one and is usually a brown slot on the main PC board. AGP slot BIOS : Basic Input Output System.
The bios is what holds the computer’s configuration and will launch the PC boot sequence on power on. This is stored in a ROM on the main board and is usually accessed for modification using the DEL key before the computer loads the operation system. BUS : This is a path on the motherboard to send data from/to peripherals, ram and cpu. Cache Memory : This is fast speed ram used by the CPU to load data faster than standard ram. Some functions and data are stored in cache. Cache is found on the main board and in the CPU itself. CD-Rom : This was the first Compact Disk standard that was used on computers to eliminate the used of 1. Floppy disks. They could hold 650MB and now up to 700MB. DVD-ROM now CD-RW : This is a CD unit that can write to blank CD’s to store data and be read on standard CD-ROMs. CPU : Central Processing Unit. This is the brain of your computer and does all the work. It’s what gets binary commands to execute with binary data. The faster the CPU, the faster the computer will be at running programs. Processor DVD-Rom : This is a cd that can read DVDs. A DVD can hold much more data than a standard CD and is mostly used to play movies. There are also some programs and games on DVD but are still rare.
DVD-RW : This is a DVD writer and like a CD-RW is used to write data on a blank DVD media. They are mostly used to make copies or movie DVDs or backup big amount of data. FireWire : FireWire is like the USB ports but faster. These are mostly used for external hard drives, DVD writers, digital cameras, scanners… they are also Plug ; Play. Firewire port Floppy Drive : Almost obsolete they are becoming an options on new computers. They can accept 1. 4 MB of data and the media is sensible to magnetic fields. Most use a cd-rom or a USB stick to carry data to other computers.
Hard Disk : This unit is the data storage of your PC for your applications, user data and all that you put on the computer. The most popular are IDE and SCSI hard disks. IDE is used for personal computers and SCSI is used more for servers. Hard disk IDE Controller : This is what you connect the hard drives to. They are usually embedded on the main board. You can add a faster IDE port card and use it in a PCI slot to connect faster hard drives or have more than 4 IDE units. ISA Slot : These were the oldest kind of slots that would take 8 or 16 bits cards. They ran at 8mhz and are still present in some computers for backward compatibility.
Printer cards or serial cards and other slow devices use these. ISA slot Keyboard : This is what you use to type. Some keyboards have extra buttons to use internet explorer functions, open the calculator and other gadgets. There are USB and PS2 keyboards. PS2 keyboard port Modem : Using a phone line this device is used to connect on the internet, send fax or other remote connections. These are slow and replaced by cable modems or ADSL for internet connections. Monitor : This is the display screen of your computer, it’s connected on the VGA adapter of your PC usually with a DB-15 cable. There are standard monitors and LCD monitors.
LCD monitor Mouse : This is what is used to move the pointer on your display screen. Some use a ball that rolls on a pad, some use infra-red and some are also wireless. Mouse pointer Network Adapter : This is the card used to connect computer together using a HUB or a network switch. If you have only two computers, you can use a crossover cable to avoid buying a HUB or switch. Twist pair NV-Ram : Non-Volatile RAM. Since computers evolve quickly and may not function with new peripherals, they replaced the BIOS ROM with NV-RAM that can be reprogrammed using a program to write the new BIOS for the main board.
Parallel Port : This is what is used to connect printers and other devices that need a faster data transfer than a serial port. They are more and more replaced by the faster USB ports and becoming an option on PC’s. Parallel port PCI Slot : Peripheral Component Interconnect. This new standard was introduced to replace the VL-BUS cards to give a faster access to the main board resources. The PCI slots on the mother board are usually white. PCI slot Plug ; Play : This came out with Windows 95. They introduced this new standard to get rid of hardware jumpers on peripherals and to make their installation easier.
It allows the computer to determine what a device is and how it uses the computer resources without creating conflicts. Port : A connection socket to plug a device to a computer. Serial port Power Supply : The supply takes 110 or 220 volts and converts it to 12v and 5v to supply the different components in the computer. Ram : Random Memory Access. This is the memory of the computer that can be read or written to by the applications. The more you have RAM the better. Random Access Memory Stores programs and data currently being used by the CPU. Measured in units called bytes.
Today’s computers carry from 250 megabytes (MB) to 2 gigabytes (GB). Synchronous Dynamic Random Access (SDRAM) – tied to the system clock so the CPU and chipset knows when to get the data. Double Data Rate (DDR and DDR2) memory – works by carrying information on the rising and falling point of a clock cycle which has double the memory bandwidth of the SDRAM. RAM Rom : Read Only Memory. ROMs are used to keep data that does not change and used by the computer when you turn it on. They can only be read and are programmed with an eprom burner at the factory. Most computers now use NV-RAM that can be reprogrammed using a little software.
Sound Card : The sound card is just to send the sound signal to a set of PC speakers or desktop theater sound system. Some will offer an amplified output, but most speaker set comes with an amplifier. They are usually stereo, four points or 5. 1 compatible depending on the specifications of the sound device. Sound card in-out USB Port : Universal Serial Bus. These are used a lot to connect keyboards, mouse, printers, digital cameras, USB sticks and many other devices without having to power down your computer. Most USB devices are detected and installed automatically using Plug & Play. USB ports
USB Stick : These are cool little memory devices that has 64, 128 … up to one meg and that you plug in a UBS port. They show in my computer as a removable hard-drive. They are very handy to carry programs or data from a computer to an other with ease since they are Plug & Play. USB memory stick Vga Card : This gives the display to your monitor. Most vga cards will fit in an AGP slot of your computer main board. There is also PCI vga cards, but these are older and are usually used as a secondary display adapter for a second monitor. VGA card VLB Card : Vesa Local BUS cards are obsolete and were replaced by PCI cards.
They were introduced to run faster than ISA cards by running at the CPU bus speed. Zip Disk : This media was basically a floppy drive that could hold more data than a standard 1. 44 floppy. It’s a magnetic media like a floppy. Hardware -The hardware are the parts of a computer. These include the Central Processing Unit (CPU), related microchips and micro-circuitry, keyboards, monitors, case and drives (floppy, hard, CD, DVD, optical, tape, etc… ). Other extra parts called peripheral components or devices include mouse, printers, modems, scanners, digital cameras and cards (sound, colour, video) etc…
Together they are often referred to as a personal computers or PCs. Central Processing Unit (CPU) refers to a specific chip, the processor. Its performance is determined by the the rest of the computers circuitry and chips. Currently the Pentium processor made by Intel is the most common processor. Many other companies, like Motorola and AMD, produce processors for personal computers. Hardware Keyboard – The keyboard is used to type information into the computer or input information. There are many different keyboard layouts and sizes with the most common for Latin based languages being the QWERTY layout (named for the first 6 keys).
The standard keyboard has 101 keys. Notebooks have embedded keys accessible by special keys or by pressing key combinations (CTRL or Command and P for example). Ergonomically designed keyboards are designed to make typing easier. Some of the keys have a special use. There are referred to as command keys. The 3 most common are the Control or CTRL, Alternate or Alt and the Shift keys though there can be more (the Windows key for example or the Command key). Each key on a standard keyboard has one or two characters. Press the key to get the lower character and hold Shift to get the upper.
Keyboard Disk Drive – image provided courtesy of commons. wikimedia. org All disks need a drive to help red information from them or write onto them. Drives are designed to correspond to the specific type of disk: CD, DVD, hard disk or floppy. Often the term ‘disk’ and ‘drive’ are used to describe the same thing but it helps to understand that the disk is the storage device which contains computer files – or software – and the drive is the mechanism that runs the disk. Disk Driver Monitor – The monitor shows information on the screen when you type. This is called outputting information.
When the computer needs more information it will display a message on the screen, usually through a dialog box. Monitors come in many types and sizes from the simple monochrome (one colour) screen to full colour screens. Most desktop computers use a monitor with a cathode tube and most notebooks use a liquid crystal display (LCD) monitor. To get the full benefit of today’s software with full colour graphics and animation, computers need a color monitor with a display or graphics card. Monitor Printer – The printer takes the information on your screen and transfers it to paper or a hard copy.
There are many different types of printers with various levels of quality. The three basic types of printer are; dot matrix, inkjet, and laser. Dot matrix printers work like a typewriter transferring ink from a ribbon to paper with a series or ‘matrix’ of tiny pins. Ink jet printers work like dot matrix printers but fires a stream of ink from a cartridge directly onto the paper. Laser printers use the same technology as a photocopier using heat to transfer toner onto paper. Printer Scanner- Allow you to transfer pictures and photographs to your computer.
A scanner ‘scans’ the image from the top to the bottom, one line at a time and transfers it to the computer as a series of bits or a bitmap. You can then take that image and use it in a paint program, send it out as a fax or print it. With optional Optical Character Recognition (OCR) software you can convert printed documents such as newspaper articles to text that can be used in your word processor. Most scanners use TWAIN software that makes the scanner accessible by other software applications. Scanner Digital Camera – Allow you to take digital photographs.
The images are stored on a memory chip or disk that can be transferred to your computer. Some cameras can also capture sound and video. Case – The case houses the microchips and circuitry that run the computer. Desktop models usually sit under the monitor and tower models beside. They come in many sizes, including desktop, mini, midi, and full tower. There is usually room inside to expand or add components at a later time. By removing the cover off the case you will may find plate covered, empty slots that allow you to add cards. There are various types of slots including IDE, ASI, USB, PCI and Firewire slots.
Digital Camera Sound Card – A photo of a sound card, an example of a computer extension card obtained from the internet Cards are components added to computers to increase their capability. When adding a peripheral device make sure that your computer has a slot of the type needed by the device. Sound cards allow computers to produce sound like music and voice. The older sound cards were 8 bit then 16 bit then 32 bit. Though human ear can’t distinguish the fine difference between sounds produced by the more powerful sound card they allow for more complex music and music production.
Sound Card Colour Card – Allow computers to produce colour (with a colour monitor of course). The first colour cards were 2 bit which produced 4 colours [CGA]. It was amazing what could be done with those 4 colours. Next came 4 bit allowing for 16 [EGA and VGA ] colours Then came 16 bit allowing for 1064 colours and then 24 bit which allows for almost 17 million colours and now 32 bit is standard allowing monitors to display almost a billion separate colours. Colour Card Memory – Core memory of a computer – Culled from the Internet There are two types of memory. he main, chip or core memory of a computer, and the basking store memory: the hard disk, DAT or other media. Memory is one of the easiest pieces of hardware to add to your computer. An example of the difference between chip memory and storage would be the difference between your office table where you do your actual work (memory) and the filing cabinet where the finished product where you file copies of your finished or pending documents (disk). Sometimes, the computer’s hard disk can be used as temporary memory when the executing program needs more than the memory on the chips can provide.
Random Access Memory (RAM) is the memory that the computer uses to temporarily store the information as it is being processed. The more information being processed the more RAM the computer needs or other software. Memory RAM memory – hips come in many different sizes and speeds and can usually be expanded. Older computers came with 512 KB of memory which could be expanded to a maximum of 640 KB. In most modern computers the memory can be expand by adding or replacing the memory chips depending on the processor you have and the type of memory your computer uses.
Memory chips range in size from 1 MB to 512 MB. As computer technology changes the type of memory changes as well making old memory chips obsolete. Check your computer manual to find out what kind of memory your computer uses before purchasing new memory chips Modem – Works with your telephone line to translate analog telephone signals into digital serial data. Also translate digital serial data into analog telephone signals. Two RJ-11 sockets – one for the modem and the other for an optional telephone so you can use the phone line to send a fax. nternal – may be used for dial up access or by the DSL connection for high speed access to the internet. external – may be a cable modem for high speed internet access. Network Card- Network Interface Cards (NIC’s) – provide an interface between the network and the PC. Types of connectors are RJ-45 (most common), BNG, 15-pin two-row DB or 9-pin female DB. Video Card- Uses a distinct 15-pin female DB connector. Power Supply – Provides the necessary electrical power to all the computer hardware components allowing them to operate. Takes standard (US) 110-volt AC power and converts it into 12-volt, 5-volt, 3. volt DC power. | Hard Drive – Store programs and data that are not being used by the CPU. Capacity is measured in gigabytes. Two common types – Enhanced Integrated Drive Electronics (EIDE) – used by 95% of all PC’s; Small Computer Systems Interface (SCSI) – show up in high-end PC’s such as network servers or graphics workstations. Motherboard -The address bus and external data bus connects the CPU to all the other computer hardware components of the system by means of the chipset. The other computer hardware components would be the video, hard drive, floppy, keyboard, sound, mouse, etc.
BIOS – Basis Input Output Service, special support programming stored on a read-only memory (ROM) chip to enable the CPU to communicate with all the components (devices) in the computer. Firmware – programs stored on ROM chips. Software – programs stored on erasable media. CMOS Group – Updated by the Setup Program which can be started in many different ways, giving access to update the computer hardware components there. Everything Else Group – Bring Your Own BIOS (BYOB) called Software Device Drivers which allow the other computer hardware components to talk to the CPU.