5-System Unit.pdf

The System Unit  Introduction Speed, capacity, and flexibility determine the power of personal computers. Knowledge of a computer’s power allows you to make good buying decisions and to determine if your current system will run new applications. Competent end users need t...

The System Unit  Introduction Speed, capacity, and flexibility determine the power of personal computers. Knowledge of a computer’s power allows you to make good buying decisions and to determine if your current system will run new applications. Competent end users need to understand the functionality of the basic components of the system unit  Electrical Safety Electrical devices have certain power requirements. AC adapters are manufactured for specific laptops. – Exchanging AC adapters with a different type of laptop or device may cause damage to both the AC adapter and the laptop. Some printer parts, such as power supplies, contain high voltage. Check the printer manual for the location of high-voltage components. Follow electrical safety guidelines to prevent electrical fires, injuries, and fatalities.  Electrical Safety ▪ Electrostatic discharge (ESD) can occur when there is a buildup of an electric charge that exists on a surface which comes into contact with another differently charged surface. ▪ ESD can cause damage to computer equipment if not discharged properly. ▪ At least 3,000 volts of static electricity must build up before a person can feel ESD. Follow these recommendations to help prevent ESD damage: ▪ Keep all components in antistatic bags until you are ready to install them. ▪ Use grounded mats on workbenches. ▪ Use grounded floor mats in work areas. ▪ Use antistatic wrist straps when working inside computers.  Electrical Safety Antistatic Bags Grounded Mats Antistatic Wrist Strap  System Unit Container that houses most of the electronic components that make up a computer system – System Chassis Personal Computer - Most widely used type of computer Five most common types Desktops Laptops Tablets Smartphones Wearable Computers 6 Form Factor of System Units The case houses the internal components such as the power supply, motherboard, central processing unit (CPU), memory, disk drives, and assorted adapter cards. The term form factor refers to the physical design and look of a case. Common desktop computers are available in form factors including: Form Factor of System Units Many case manufacturers may have their own naming conventions, including full tower, mid tower, mini tower, HTPC case, rack-mount, and more. System Unit Types 1. Desktops System unit is in a separate case Tower Units All-in-Ones All components including monitor 2. Laptops Portable and much smaller Two-in-one laptops Ultrabooks Gaming  System Unit Types 3. Tablet or Tablet Computer Mini tablet 4. Smartphone Most popular device – handheld computer Extend the capabilities of cell phones 5. Wearables Contain embedded computers Smartwatch Activity Trackers  Gaming Console gaming Mobile gaming PC gaming  Components Although all devices come in many shapes and sizes, they have similarities such as – System boards – Microprocessors – Memory  System Board System board or main board or motherboard controls communication for the entire computer system All components and devices connect to the system board Data path and traffic monitor – Allows various components to communication efficiently with one another Sockets and Chips The system board contains a variety of electronic components Sockets – the connection point for chips Chips – Tiny circuit boards etched onto squares of silicon – Also called silicon chip, semiconductor, or integrated circuit – Mounted on chip carriers  Slots and Bus Lines Additional system board components: Slots – Provide a connection point for specialized cards or circuit boards – Provide expansion capabilities for the computer Bus lines – Connecting lines that provide pathways to support communication among electronic components  Microprocessor Central Processing Unit (CPU) or Processor – Contained on a single chip call a Microprocessor – Brain of the computer Two Basic Components of the CPU – Control unit (CU) Tells the computer system how to carry out a program’s instruction – Arithmetic-logic unit (ALU) Performs arithmetic and logical operations 16 Microprocessor Chips Chip capacities are expressed in word size – Word size is the number of bits that can be processed at one time: 16, 32 or 64 Clock Speed – Processing speed or the number of times the CPU fetches and processes data or instructions in a second Unit Speed Microsecond Millionth of a second Nanosecond Billionth of a second Picosecond Trillionth of a second Femtosecond Quadrillionth of a second  Multicore Chips – Multicore Processors Two or more separate and independent CPUs within a system unit Processor Manufacturer – Quad-core supports 4 core processes A-Series AMD – Parallel Processing E-Series AMD Computer’s ability to divided tasks into parts that can be distributed Atom Intel across each core i7 Intel Windows 10 and macOS High Sierra support parallel processing Specialty Processors Coprocessors – Designed to improve specific computing operations – Graphics Processing Unit (GPU) / Graphics coprocessors – Designed to handle a variety of specialized tasks 3D images Encrypting data Standard features in gaming computers  Memory Holding area for data, instructions, and information Contained on chips connected to the system board Three well-known types of memory chips: – RAM Random Access Memory – ROM Read Only Memory – Flash Memory  RAM Random Access Memory (RAM) chips hold programs and data that the CPU is presently processing – Volatile or temporary – contents are lost when computer is powered off Cache memory – temporary, high-speed holding area between the memory and CPU – Additional RAM can be added using an expansion module called a DIMM (Dual in-line memory module)  RAM Virtual Memory – Dividing a program Unit Capacity between memory Megabyte (MB) 1 million bytes and storage enabling the system to run Gigabyte (GB) 1 billion bytes very large programs Terabyte (TB) 1 trillion bytes Petabyte (PB) 1 quadrillion bytes Memory is expressed in bytes  ROM Read-only memory (ROM) – Information stored by the manufacturer – Non-volatile and cannot be changed CPU can read, or retrieve data and programs in ROM but the computer cannot change ROM Contain special instructions – Start the computer – Access memory – Handle keyboard input  Flash Memory Flash memory combines the features of: – RAM, it can be updated – ROM, it is non-volatile – Commonly used in SSD USB drives Memory cards BREAK Expansion Slots and Cards Expands your system’s capabilities Graphics cards for high quality 3D graphics Network interface cards (NIC) connect devices to networks via cables Wireless network cards connect devices to networks without cables SD cards – Expansion cards for mobile devices  Expansion Slots and Cards Graphics Cards NIC Wireless Network Cards SD Cards  Bus Lines / Bus Connect parts of the CPU to each other and various other components on the system board Pathway for bits representing data and instructions Bus width – Number of bits that can travel simultaneously down a bus Architecture and design are tied to the speed and power for the computer Two basic categories of buses – System bus – connects CPU to memory – Expansion bus – connects CPU to other components  Expansion Buses It connects the CPU to slots on the system board. Types of expansion buses: industry standard architecture (ISA) peripheral component interconnect express(PCIe) accelerated graphics port (AGP) universal serial bus (USB) FireWire buses  Ports Socket for connecting external devices to the system unit Ports connect directly – To the system board – To cards inserted into slots on the system board Two Types – Standard Ports – Specialized Ports  Standard Ports USB – Keyboards, mice, printers, storage devices Ethernet – High speed networking HDMI – High Definition Multimedia Interface – High definition video and audio Thunderbolt – Provides high-speed connections – Can connect up to 7 separate devices through 1 port  Standard Ports USB Ethernet HDMI Thunderbolt  Specialized Ports External Serial Advanced Technology Attachment (eSATA) – High-speed connection for external secondary storage Musical Instrument Digital Interface (MIDI) – Connect musical instruments Mini DisplayPort (MiniDP or mDP) – Connection to large monitors VGA (Video Graphics Array) & DVI (Digital Visual Interface) – Connections to analog and digital monitors FireWire – High-speed connections to FireWire devices Specialized Ports eSATA MIDI MiniDP VGA FireWire  Cables Used to connect external devices to the system unit via the ports One end of the cable is attached to the device and the other end has a connector that is attached to a matching connector on the port  Power Supply Computers require direct current (DC) power converting alternating current (AC) from wall outlets or batteries – Desktop computers have a power supply unit in the system unit – Laptops use AC adapters in the system unit – Tablets and mobile devices use internal AC adapters – Smartphones can use wireless charging platforms Electronic Data and Instructions Digital electronic signals – Recognized by computers Analog signals – Continuous signal – Created by voices Conversion must take place from analog to digital before processing can occur Numeric Representation Two-state binary system consists of only two digits called bits – On = 1; negative charge – Off = 0; no charge Byte = 8 bits grouped together Hexadecimal system – Uses 16 digits to represent binary numbers (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F) Numeric Representation Character Encoding Character encoding standards assign a unique sequence of bits to each character ASCII – American Standard Code for Information Interchange – Used by personal computers EBCDIC – Extended Binary coded Decimal Interchange Code – Used by mainframe computers Unicode – New encoding due to explosion of the Internet – Uses 16 bits – Recognized by virtually all computer systems ASCII TABLE  UNICODE With Unicode each character uses a unique number between U+0000 and U+10FFFF Unicode may be 8-bit, 16-bit, or 32-bit. Example text: Computer Hope Unicode: U+0043 U+006F U+006D U+0070 U+0075 U+0074 U+0065 U+0072 U+0020 U+0048 U+006F U+0070 U+0065 UNICODE TABLE