Computer Performance & Storage Devices Computer Technology Part 3 Megan Rees ERMS 12/13 Part 3

Computer Performance Megan Rees ERMS 12/13 Part 3

Boot Process Sequence of events that occurs between the time you turn on a computer and the time that it becomes ready to accept commands. Purposes Runs a diagnostic test to make sure everything is working. Loading the operating system, so the computer can carry out basic operations. Megan Rees ERMS 12/13 Part 3

6 events of the boot process: Power up Start boot program Power-on self-test Identify peripheral devices Load operation system Check configuration and customization Megan Rees ERMS 12/13 Part 3

Circuits The path from one component of a computer to another that data uses to travel. Circuits run between RAM and the microprocessor RAM and various storage devices Megan Rees ERMS 12/13 Part 3

Silicon Chip Silicon is melted sand. What the circuits are embedded into to keep them together. Megan Rees ERMS 12/13 Part 3

Megahertz (mHz) A measurement used to describe the speed of the system clock. A megahertz is equal to one million cycles (or pulses) per second. 1.3 GHz means that the microprocessor’s clock operates at a speed of 1.3 BILLION cycles per second. Megan Rees ERMS 12/13 Part 3

RAM vs. ROM System Crash! ROM RAM Megan Rees ERMS 12/13 Part 3

RAM vs. ROM RAM RAM Read Only Memory Random Access Memory Temporary—content is lost if the device is powered off Runs all currently open programs – the more open programs the slower your computer is RAM is rather inexpensive—getting more RAM can speed up your computer. But there is a limit to how much RAM your computer can have. Read Only Memory Permanent Storage Where all your programs and files are saved—your hard drive. The bigger your hard drive, the more you can save there. Hard drives rarely crash—anything saved there is pretty safe—but it’s always good to have backups! Megan Rees ERMS 12/13 Part 3

Binary Number System A method for representing letters or numbers using only two digits, 0 and 1. Bit Each 0 or 1 Byte 8 bits Also referred to as Base 2 Binary Code. Megan Rees ERMS 12/13 Part 3

Byte Kilobyte Megabyte Gigabyte Terabyte Memory Measurements Bit Each 0 or 1 Byte 8 bits Kilobyte Approximately 1,000 bytes Exactly 1,024 bytes Megabyte Approximately 1 million bytes Exactly 1,048,576 bytes Gigabyte Approximately 1 billion bytes Terabyte Approximately 1 trillion bytes Petabyte, Exabyte, Zettabyte, Zottabyte, Brontobyte Megan Rees ERMS 12/13 Part 3

Storage Devices Used to keep data when the power to the computer is turned off. Medium/media Location where data is stored. Write-Protected - A disk that will not allow a user to make changes to files Megan Rees ERMS 12/13 Part 3

Hard Disk Usually mounted inside the computer’s system unit. Can store billions of characters of data. Stated in forms of bytes: Megabytes or Gigabytes Megan Rees ERMS 12/13 Part 3

USB Flash Drive Also known as a “Jump Drive.” Typically removable and rewritable, physically smaller than a floppy. Storage capacities can be as large as 256 GB. Most are 2 to 8 GB. Smaller, faster, thousands more times capacity, and are more durable and reliable. Plug right into a USB port. Megan Rees ERMS 12/13 Part 3

Memory Card Used for storing digital information, usually for digital camera, mobile phones, laptops, MP3 Players, and video game consoles. Small, re-recordable and can retain data without power. Usually store from 2 to 8 GB. Megan Rees ERMS 12/13 Part 3

Optical Storage Means of recording data as light and dark spots on CD or DVD. Reading is done through a low-power laser light. Pits Dark spots Lands Lighter, non-spotted surface areas Megan Rees ERMS 12/13 Part 3

CD-ROM “CD – Read Only Memory” Also called CD-R Storage device that uses laser technology to read data that is permanently stored on compact disks, cannot be used to write data to a disk. Megan Rees ERMS 12/13 Part 3

CD-RW “CD-Read Write” A storage device that reads data from CD’s and also can write data to CD’s. Similar to a CD-ROM, but has the ability to write to CD. Megan Rees ERMS 12/13 Part 3

DVD-ROM “Digital Video Disks – Read Only Memory” Reads data from CD’s (audio and data) and DVD’s (data or movie) Cannot be used to write data to a disk. Megan Rees ERMS 12/13 Part 3