Computer Hardware
Topic 3

Computer Hardware

1. Computers can only do three things

   1. Store and retrieve data; data is information

   2. Manipulate the data; math and logic functions

   3. Move data from one device to another; Movie - DVD drive to a monitor

2. Computers have two components

   1. Software - programs for the computer; tells computer how to process information

   2. Hardware - physical devices

      1. Light Crystal Display - displays information

      2. CD-Rom and DVD drives - device that reads optical disks

         1. Devices tend to be slow

         2. Used to store data

      3. Hard drive - stores large volume of data

         1. Very slow

         2. Very reliable

      4. Keyboard, mouse, etc.

3. Internal hardware connect on a motherboard

   1. Central processing Unit (CPU) - process the information

      1. Brain of the computer

      2. Processor

         1. Speed - defined in megahertz or gigahertz

         2. Mega is million and giga is billion; the old days it was kilo, or thousands

         3. The time for a computer to process instructions

            1. Important but not reliable

            2. CPU can execute multiple instructions at the same time

               1. 2.1 gigahertz AMD processor

            3. CPU has 2,100,000,000 cycles per second

   2. Rapid Access Memory (RAM) - temporary memory for the computer

      1. Directly connected to the CPU

      2. RAM is very fast; programs are loaded from other devices to RAM

      3. CPU gets its information from the RAM

      4. RAM has speed and capacity

         1. The more the better until you hit a limit

         2. Speed ranges from 100 MHz to 1,000 MHz

         3. Double Data Rate (DDR) - DDR, DDR2, and DDR3

   3. The Chip set

      1. Northbridge - a chip that connects the CPU to the RAM and display chip

         1. Very fast

         2. Two designs - the video chip needs memory for display information

            1. The CPU and display chip share the RAM

               1. Slows down the system

               2. Many laptops and low budget computers

            2. The display chip has its own memory

               1. System if very fast

               2. Gaming laptops; more expensive

               3. Laptops - the display chip is inside the north bridge

      2. Southbridge - a chip that connects the other devices, like keyboard, sound, network card, etc.

         • Tends to be slower

Web Browsers and Websites

1. CPU Types

   1. Desktop and laptops

      1. AMD; 15.8% market share

         • Athlon

         • Turion

         • Semprom (budget)

      2. Intel; 82.6% market share

         • Pentium

         • Celeron (budget)

         • Atom - small computers

   2. Cellphones, Ipods, Epads, etc

      1. Reduced Instruction Set Computing (RISC) - CPUs has small instruction sets, power efficient, and small

      2. Includes the ARM processors

      3. Operating systems

         1. Cannot run Windows, except Windows CE

         2. Google Android / Iphone

         3. Ubuntu - Linux

2. CPUs are restricted in frequency

   1. Frequency is important for speed

      • CPUs are complex; can perform several instructions at one time

      • Difficult to compare 2.0 GHz Athlon and Pentium

   2. CPUs do not exceed 3.5 GHz

      • Note - IBM mainframe has CPUs with 5.2 GHz

      • The faster the CPU, the hotter it gets

      • Laptops - CPU can adjust its frequency to keep it cool