HARDWARE Rashedul Hasan.
HARDWARE Hardware is the Tangible part/s of the computer. Along with the Processor, RAM, CD-ROM and Input & Output devices, it includes, • Motherboard • Power Supply • Graphics card • Sound card • Modem
Motherboard • The motherboard is sometimes alternatively known as the main board. • A motherboard provides the electrical connections by which the other components of the system communicate. • Microprocessor, main memory, External storage, sound card, Modem etc. can attach with the Motherboard.
Motherboard includes, • Sockets (or slots) in which one or more microprocessors are installed. • Slots into which the system's main memory is installed (typically in the form of DIMM modules containing DRAM chips) • A chipset which forms an interface between the CPU's front-side bus, main memory, and peripheral buses. • Non-volatile memory chips (usually Flash ROM in modern motherboards) containing the system's BIOS
Motherboard includes, • A clock generator which produces the system clock signal to synchronize the various components. • Slots for expansion cards. • power connectors flickers, which receive electrical power from the computer power supply and distribute it to the CPU, chipset, main memory, and expansion cards. • Additionally, nearly all motherboards include logic and connectors to support commonly-used input devices, such as PS/2 connectors for a mouse and keyboard.
BIOS/BOOTING • Motherboards contain some non-volatile memory to initialize the system and load an operating system from some external peripheral device. • Most modern motherboard designs use a BIOS for booting purpose.
POST • By booting the motherboard, the memory, circuitry, and peripherals are tested and configured. This process is known as a computer Power-On Self Test (POST) and may include testing some of the following devices: • floppy drive • network controller • CD-ROM drive • DVD-ROM drive • Hard drive • External USB memory storage device
Ports & Classifications of Ports A port is a connecting socket. Classification of Ports: • Serial Port: Used for transmitting slow data over long distance. It acts like cars on a one-lane highway as individual bits must follow each other. It usually connects Keyboard, Mouse, Monitors and modems etc.
Port • Parallel Port: Used for transmitting fast data over short distance. A line connected to this port can transmit 8 bits (1Byte) simultaneously. It acts like cars on a eight-lane highway as individual bits do not need to follow each other.
Port • SCSI Port: Small computer system interface post allows data to be transmitted at a speed 32 bits at a time. It may use to connect external hard drive, CD-ROM, Scanner etc. • USB Port: This port are useful for peripherals such as digital camera, pen drive, high speed Modem, Scanner etc.
Port • Dedicated Port: This are the ports for special purpose. For example for connecting keyboard, Mouse etc. • Infrared Port: Used for Wireless connection over a few feet. For example, wireless keyboard, wireless mouse etc.
Expansion Vs. Upgrade • Expansion is the way of increasing computer’s capabilities by adding hardware. for example, adding one more RAM. • Upgrading means changing to newer, usually more powerful or sophisticated version. for example, changing to more powerful processor.
Expansion Bus • ISA Bus: Industry Standard Architecture bus is used for ordinary low-speed transmission. It is the oldest and at 8 to 16 bits, the slowest at transmitting data. • PCI Bus: Peripheral Component Interconnect Bus is a higher speed Bus, and at 32 to 64 bits wide it is four times faster than ISA Bus. It is usually connects graphics card, modems, sound card etc.
PCI Bus • PCI (being phased out for graphic cards but still used for other uses). The Peripheral Component Interconnect, or PCI Standard, specifies a computer bus for attaching peripheral devices to a computer mother board. Typical PCI cards used in PCs include: network cards, sound cards, modems, extra ports such as USB or serial, TV tuner cards and disk controllers.
Expansion Bus • AGP Bus: The Accelerated Graphics Port Bus can transmit data at even higher speeds and was designed to support video and 3D graphics. An AGP Bus is twice as fast as a PCI Bus.
Power Supply • A device that converts one form of electrical power to another form and voltage. • This typically involves converting 120 or 240 volt AC power to a lower voltage DC power to run computer. • The on/off switch in your computer turns on or shuts off the electricity to the power supply.
Graphics Card • A video card, also known as a graphics accelerator card, display adapter, or graphics card, is an expansion card whose function is to generate and output images to a display. For example AGP card.
Sound card • A sound card (also known as an audio card) is used to transmit digital sounds through speakers, microphone and headset.
Sound cards usually feature a digital-to-analog converter, that converts recorded or generated digital data into an analog format. • The output signal is connected to an amplifier, headphones, or external device using standard interconnects.
Sound channels and polyphony • An important characteristic of sound cards is polyphony, which is more than one distinct voice or sound playable simultaneously and independently, and the number of simultaneous channels. • Sound channels may correspond to a speaker configuration such as 2.0 (stereo), 2.1 (stereo and sub woofer), 5.1 etc.
Modem • Modem means Modulator-Demodulator. • Modulate: Converts digital signals to analog form • Demodulate: Converts analog signals back to digital form
MODEM because telephone lines have traditionally been analog, we need to use modem if our computer is to send signals over a telephone line. The modem converts the computer’s digital signals into telephone line’s analog signals and analog signals back into digital signals. Modem means Modulator demodulator. Modems are rated by their speed in moving data from the computer to the telephone line. This speed is measured in bits per second (bps). Standard modern modems are rated at 28,800 bps, 33,600 bps and 56,400 bps.