The Components of a System Unit

Buffering often happens between lines. Pipelining Data Pipelining is set up to allow one computer’s output is the next computer’s input. Buffering often happens between lines. In other words, it is an assembly line way of thinking for a computer’s output/input.

Registers Registers are high speed storage units. Help keep processing efficient to hold temporary instructions Are not part of memory or permanent storing devices.

System Clock The system clock is a small quartz crystal circuit used to control the timing of all the computer operations. Each tick is equal to a ‘clock cycle’. They are often superscalar, which means they can do more than one thing at a time. They are measured by ‘clock speed’, or by ticks per second. PCs have gigahertz range clock speed (or one billion ticks per second).

PC Processors Intel -chips power 85% of laptops -major producer of boards, systems, and software -developed the world’s first processor in 1971 AMD -2nd largest manufacturer of processors for Windows capable computers -paramedic superiority -guarantees it’s microchips meet or exceed standards Motorola -PowerPC -low priced -Used in Apples -faster clock speeds -consume less power (small) Alpha -used in workstations -high-end servers -improved multimedia -wireless capabilities -extended battery life

Comparing Personal Computers The lead processor chip manufactures for personal computers are Microsoft, AMD, IBM, Motorola, and Transmeta.

Cooling Machines Some computers use liquid cooling technology. This reduces the temperature of the processor. It uses liquid like water continuously to carry the heat away to a radiator-type grill that cools down the liquid and takes it back to it’s original location.

Processor Installation Upgrades What you will need: -Screwdriver -CPU Heat Sink/Fan -Heat Sink Compound -Processor http://youtu.be/FyK-roVdx7c

System Unit The system unit is a case that contains electronic components of the computer used to process data. Also called the chassis All computers have them Common Components: Processor Memory Module Expansion Cards (Sound, modem, video, and network interface cards) Ports and connectors

Motherboard The motherboard is the main circuit board in the system unit. Also called a system board Many electronic components attach or are built into the motherboard Expansion cards Processor Chip Memory Module

Central Processing Unit Also called the processor or CPU The CPU interprets and carries out the basic instructions that operate a computer Most devices communicate with the CPU in order to carry out a task Contains a control unit and an arithmetic logic unit that work together to perform processing operations

Control Unit The control unit is the component of the CPU that directs and coordinates most of the operations in the computer. It interprets each instruction issued by a program and then starts the appropriate action to carry out the instruction

Arithmetic Logic Unit The arithmetic logic unit (ALU) is a component of the processor that performs arithmetic, comparison, and other operations. Arithmetic operations: addition, subtraction, multiplication, division Comparison: determines if one data item is greater than, less than, or equal to another

Expansion Slots Allows you to add more memory to a computer as well as a sound or video card The expansion cards plug directly into the expansion slots in the motherboard Pcle (PCI Express), PCI, AGP, and ISA are all common types of expansion slots located in the PC.

Expansion Cards They allow you to add additional functions to your computer to help it do something. Commonly referred to as: Add-on card Internal card Interface adaptor Types of expansion cards include: Interface card Modem MPEG Decoder Network Card Sound/Video Card Video capture card

PC Cards A PC Card is: a printed circuit board for a personal computer These are originally known as PCMCIA cards which is short for Personal Computer Memory Card International Association Was originally designed for a basic memory-expansion card Usually the same size as a credit card

Ports Serves as an interface between the computer and other peripheral devices. Specialized output on equipment to which a plug or cable connects. Can be either male or female, but female ports are more common. Variety of shapes such as round, rectangular, square, or trapezoidal.

Special Purpose Ports Allow users to attach specialized peripherals Attach to digital video cameras, color printers, scanners, and disk drives transmit data to wireless devices Types are MIDI, eSATA, SCSI, IrDA, bluetooth port, firewall Port

Types of Expansion Buses Expansion bus: a type of bus that allows the processor to communicate with peripheral devices Expansion bus type determines the type of expansion card you can add Types of expansion buses: ISA (Industry Standard Architecture) Local Bus VESA local bus PCI (Peripheral Component Interconnect) AGP (Accelerated Graphics Port) USB (Universal Serial Bus) PC card bus

Bays Bay: open area inside the system unit used to install additional equipment Drive bays: Used for disk drives External (exposed) drive bay Can be accessed from outside the system unit Examples: DVD-ROM drive, CD-RW drive, floppy disk drive, Internal (hidden) drive bay Completely concealed within the system unit Hard disks drives are installed in internal bays

Power Supply Most personal computers plug into standard wall outlets, which supply an alternating current (AC) of 115 to 120 volts. This type of current will not power a computer, which requires a direct current (DC) from 5 to 12 volts Power Supply: the component of the system unit that converts the wall outlet AC power into DC power AC adapter: an external power supply that converts power for external peripheral devices such as an external modem, speakers, or a tape drive One end plugs into the wall outlet and the other end attaches to the peripheral

Buses Bus: electrical channel that allows various devices inside the computer to communicate with each other Bus width (the size of the bus) determines the number of bits that can be transmitted at one time Word size: the number of bits the processor can interpret and execute at a give time (usually the same as bus width)