Expansion cards

The expansion card (also expansion board, adapter card or accessory card) in computing is a printed circuit board that can be inserted into an expansion slot of a computer motherboard or backplane to add functionality to a computer system via the expansion bus.
One edge of the expansion card holds the contacts (the edge connector) that fit exactly into the slot. They establish the electrical contact between the electronics (mostly integrated circuits) on the card and on the motherboard.

Parts of a computer

If you use a desktop computer, you might already know that there isn't any single part called the "computer." A computer is really a system of many parts working together. The physical parts, which you can see and touch, are collectively called hardware. (Software, on the other hand, refers to the instructions, or programs, that tell the hardware what to do.)

The illustration below shows the most common hardware in a desktop computer system. Your system may look a little different, but it probably has most of these parts. A laptop computer has similar parts but combines them into a single notebook-sized package.

Desktop computer system

Let's take a look at each of these parts.

Parts of the Motherboard

PCI (Peripheral Component Interconnect) Slot: Supports peripherals like sound cards, DVD decoders, and graphic accelerators with 32 bits at 33Mhz capabilities. There are usually anywhere from 1 to 6 PCI slots available on the motherboard. (LAN card, Sound Card, MODEM Card, USB Card)

AGP (Accelerated Graphic Port): This provides fast bus speed connectivity along with fast access to the main memory. It is designed for video cards that demand higher bandwidth.

Chipset-North Bridge: An integrated circuit that has special duties. connects the processor, memory and video card.

Chipset-South Bridge: connects all the peripherals whether it is connected using USB, ISA, and PCI connector.

CPU (Central Processing Unit) Socket: A socket specifically for connecting your computer processor.

Memory -

(Double Inline Memory Module) slots, SIMM (Single Inline Memory Module) and RIMM: Different types of memory (RAM) can be installed into these slots.

Motherboard Battery: A battery compartment, which stores the battery used for storing data such as system date and time, when you shut down your system.

IDE Connector: Responsible for connecting the IDE cord used for hard disks, CD drives, and DVD drives.

Internal Components of Computer

 

Internal Components of Computer

• Power Supply/PSU – power supply unit, converts outlet power, which is alternating current (AC), to direct current (DC), which is what the internal components require, as well as providing appropriate voltages and currents for the various internal components.

• Motherboard/mainboard – As the name indicates, this is the electronic centerpiece of the computer; everything else connects to the motherboard.

• Processor/CPU – central processing unit, the "brain" of the computer, most actual computation takes places here.
• Heat Sink /CPU Fan - is an environment or object that absorbs and dissipates heat from another object using thermal contact (either direct or radiant).

• RAM/Memory – random access memory, the "short-term memory" of a computer, used by the CPU to store program instructions and data upon which it is currently operating. Data in RAM is lost when the computer is powered off, thus necessitating a hard drive.

• Hard Drive/Hard Disk – the "long-term memory" of the computer, used for persistent storage – i.e. the things stored on it remain even when the computer is powered down. The operating system, and all your programs and data are stored here.

• Optical Drive (CD-ROM) – device for reading/writing optical disks. May read CDs, DVDs, or other optical media, depending on the type. It is essential for installing many operating systems and programs. It may be able to write some of these discs, as well. Some people like to have two such drives for copying disks.

• Video Card/Graphics Card– does processing relating to video output. Some motherboards have an "onboard" GPU built in so you don’t need (but may add) a separate video card.

Computer Back Panel

System Unit/Back Panel

– is the most complicated part of a PC. It houses the actual computing power of the system, provides connections to all the peripherals, and holds the disk drives where you insert removable storage media such as CDs and floppy disks.

Ports - a generic term for connection points.

Power Input      

- is where you plug in the PC’s electrical power cord.

Mouse port

- this dedicated port is just for the mouse.

Keyboard port

– this special dedicated port is just for the keyboard.

USB ports

– universal serial bus (USB) ports are general-purpose connectors found on newer PCs. The more unusual the peripheral, the more likely it will use USB port.

 

Serial ports

– these 9-pin connectors is one of the oldest and most universal port found in the back of a PC. Before the introduction of USB in the mid 1990s, serial ports where heavily used.

 

Parallel port

– virtually as old as the serial port, the 25–pin parallel port has been updated a number of times over the ye3ars. Despite the growing prominence of USB, parallel ports remain a popular means for connecting printers.

 

Video port

– this unique three-row, 15-pin connector is where the monitor connects to the system unit.

 

Audio ports

– these are used to connect speakers, microphones, and other audio devices.

 

 Game port

– also known as a joystick port, this 15-pin connector can be used both for joysticks and for MIDI musical devices.

 

Modem port

– this looks like a telephone jack, and for a good reason – that’s what’s it is. Modem enables your computer to communicate with other computers via telephone line. Notice that there are two connectors. One is an IN jack, and the other is an OUT jack, which you can use to plug in a telephone.

 

Network interface/LAN Port

– the network interface is normally called just that, and not a port. It is sometimes referred to as an Ethernet connector. It connects your PC to other PC’s in a Local Area Network.