Computer Hardware Basics

• Computer Applications
• Chapter 1: Computer Terminology & Organization, Computer Peripherals
• Maria Raidy
• CSC 201 - Computer Application

Bits vs. Cells and Atoms

• Data in a computer is made of bits.
• Humans consist of cells and objects consist of atoms.

What is a Bit?

• A bit is the smallest data form that has only 2 values (binary).
• It is either a 1 or 0.
• Bits can be lined up in a sequence to represent other data.
• Example: 101011101000110

Byte

• Bytes are the standards measurement units for size in computers.
• 8 bits form a byte.

The Measurements of Sizes

• 1 Byte = 8 bits
• 1 Kilobyte = approximately 1,000 Bytes
• 1 Megabyte = approximately 1,000,000 Bytes (Million)
• 1 Gigabyte = approximately 1,000,000,000 Bytes (Billion)
• 1 Terabyte = approximately 1,000,000,000,000 Bytes (Trillion)

Converting a Byte into a Number

• This method works for any binary number like 10101001.
• Write the powers of 2 starting from the right with 2⁰.
• Add only the numbers that have a 1 under them to get the decimal equivalent.
• For example, 10101001 = 128+0+32+0+8+0+0+1 = 169

The PC's Anatomy

• Human anatomy is linked to elements of the PC's anatomy.
• The brain is linked to the CPU.
• The pocket is linked to storage devices (hard disk drive).
• Short-term memory is linked to RAM.
• Long-term memory is linked to the cache.
• The eyes are linked to the video card/graphic card.
• Spinal cord is linked to the motherboard.

CPU (Central Processing Unit)

• The CPU handles every piece of data that is processed by the PC.
• The CPU is the central brain of the PC.

CPU Manufacturers and Speed

• Two main manufacturers of CPUs are Intel and AMD.
• Intel: Pentium, Centrino, QuadCore, Core i7, etc.
• AMD: Athlon, Turion, Phenom, etc.
• CPU speed is measured in Hz, with current PCs using GHz (GigaHertz).
• Development is focused on more "Cores" instead of faster CPU speeds.

Multicore CPU

• Each core in the CPU can process calculations independently.
• Multicore CPUs can reduce processing time when multiple applications are being used.
• A multicore CPU with a speed of 1.5GHz has that speed for each core.
• A dual core does not add upto 3GHz and a quad core does not add upto 6Ghz.

The Cache

• Cache is a defining factor other than speed and the number of cores.
• Cache is a buffer zone that keeps the data to be calculated by the CPU.
• A larger cache allows the CPU to handle more data at a time.
• Current sizes of cache are in MBs (MegaBytes).
• When a processor needs to read or write, it checks for data in the cache first

The RAM (Random Access Memory)

• RAM stores all the resources and data that are needed by the application you are currently using.
• Once the application is closed, it is removed from RAM.
• RAM is volatile.
• RAM is measured by its size in Bytes (MBs, GBs) and speed in Hz or cycles per second.
• RAM is made of pure electricity.
• Data in RAM is lost when electricity to system is switched off.

Storage Devices

• There are currently 2 types of storage devices used: hard disk drives (HDD) and solid state drives (SSD).
• There are also removable storage devices such as CDs, DVDs, flash USB drives and external hard disks.
• Storage Devices have limited Write/Erase Lifetime.

Hard Disk Drives

• Hard disk drives (HDDs) are permanent storage devices used for keeping all files.
• They are defined by their size in Bytes (GBs and TBs), speed in rpm, and buffer in MBs.
• Higher buffer leads to better feed.
• Standard RPMs include 4200, 5400, 7200, and 10000.

Solid State Drives

• Solid state drives (SSDs) are the latest technology in storage devices.
• They work the same way as flash disk drives, meaning that data is stored on chips instead of disks.
• Solid state drives are known to have way better (reading) speeds, since they work on electricity similar to RAM.

Storage Drives (RAID)

• Redundant Array of Independent Disks (RAID) technology uses multiple hard disk drives to back up data or make the read/write process faster.
• RAID 0: Data is distributed across several disks, improving speed and capacity but all data will be lost if any disk fails.
• RAID 1: Two or more disks each store exactly the same data.

How a Software Loads

• Data goes from the Storage Device (HDD or SSD) to the RAM, then to the Buffer, before finally being processed by the CPU.

Video Card

• The Video Card or Graphics Accelerator Card is used to generate and output images to a display.
• It is its own independent component.
• It computes the data related to the images and videos seen on a Screen.
• The video card has its own set of RAMs to be used as memory.
• The video card uses a GPU (Graphics Processing Unit) to compute the data in the best manner for images and videos and games.

Graphic Cards Companies

• Three manufacturers for GPUs and graphics cards include Intel, nVidia, and AMD.
• nVidia has the GeForce series and AMD was formerly known as ATI.
• Intel is known to not have powerful graphics.
• nVidia and AMD are dedicated companies to graphics cards.

The Motherboard

• The motherboard connects all the components of a PC.
• The motherboard is the spinal cord of the PC
• The motherboard contains slots for the CPU, RAM, video card, hard disk, CD/DVD ROMs, etc.

Computer Peripherals

• A peripheral is computer hardware that is added to a host computer.

Optical Disc Drives

• Used to read and/or write on different "Optical Discs"
• There are Reader Drives (ROM) and Writer Drives (Burners)
• Optical Disk Drives read different Optical Disks or even burn them

The Compact Disc

• Compact disk (CD) is a type of optical disc that is flat and round, and is used to store digital data.
• CD: Compact Disc
• The Size of a CD is 700 MBs
• Optical Disc Drives include: CD-ROM, CD-R, CD-RW
• The compact disc is resistant to scratches given how it writes at the deepest layer of the disc.

The DVD

• DVD: Digital Versatile Disc OR Digital Video Disc
• Size: 4.7 GBs
• Optical Disc Drives: DVD-ROM, DVD-R, DVD-RW, DVD+R, DVD+RW, DVD±RW
• DVDs can be of more size due to Dual Layer technology.
• It can hold 8.54 GBs per side.
• Such DVDs require Dual Layer DVD Recorders.

Dual Layered Technology

• Dual Layer technology provides two individual recordable layers on a single sided DVD disc.
• To take advantage of dual layer technology when recording DVDs, you must use a dual layer enabled DVD burner and dual layer DVD media.
• Dual Layer is more commonly called Double Layer and can be written as DVD+R

The Blu-Ray Disc

• Size: 25 GBs (50 GBs if Dual Layer)
• Optical Disc Drives: BD-ROM, BD-R, BD-RE
• Blu-Ray Discs are known to be the next step into Home Video where High Definition plays an important role.
• Blu-Ray offers more than five times the storage capacity of traditional DVDs.
• The single-layer disc holds up to 25GB, the dual-layer disc holds 50GB.

The Universal Serial Bus (USB)

• The Universal Serial Bus (otherwise known as USB) is a connection type used to connect peripherals to the computer.
• It was created first in January 1996.
• The Technology started with version 1.0, and then went on to 1.1, 2.0 and USB 3.0.

USB 1.0 and 1.1

• The first USB devices were released in 1996 with USB 1.0 at a speed of 1.5 Mbit/s (Low-Speed) and 12 Mbit/s (Full-Speed).
• In 1998, USB 1.1 fixed problems with USB hubs.

USB 2.0

• USB 2.0 was released in 2000 with a transfer speed of 480 Mbit/s (Hi-Speed).
• USB 2.0 is multipurpose
• It is the technology used for flash drives, mini-heating devices, and battery charging.

USB 3.0

• USB 3.0 is the latest version in the market.
• It has a transfer rate of 5.0 Gbit/sec.
• USB 3.0 receptacles are compatible with USB 2.0 device plugs for the respective physical form factors.

Monitors

• From Cathode Ray Tube (CRT), to Liquid Crystal Display (LCD), to Light Emitting Diode (LED)
• From CRT to LCD to LED

The CRT Monitor

• CRT stands for Cathode Ray Tube .
• It is equivalent to the old TV technology originally created in 1897.
• It is has high refresh rates (85 Hz ~ 100Hz) which help in reducing flickering.

CRT

• A cathode ray tube (CRT) monitor is an analog computer display or television set with a large, deep casing.
• Monitors use streams of electrons that activate dots/pixels on the screen to create a full image.
• Advantages include the range of colors that can be displayed.
• CRT monitors also have wider viewing angle and are usually less expensive than similarly sized LCD models.

Refresh Rate

• The refresh rate is the number of times in a second that a display hardware draws the data it is being given.
• The higher the refresh rate the more the eye feels relaxed on the long run.

The LCD Monitor

• LCD (or Liquid Crystal Display) is another kind of monitor which is widely used today and has replaced the CRT, whether for PCs or TVs.
• It is known to be still not so cheap (at least not as much as CRT) and has lower refresh rates (60 Hz at low resolutions, 120 Hz at high resolutions).

LCD Advantages

• LCDs are smaller and lighter than CRTs, making them better for small offices.
• They also give less glare and consume less power than CRT monitors.
• LCDs have no flicker problems and run quite well at lower refresh rates.

The LED Monitors

• LED (Light Emitting Diodes) Flat panels consume less than half the power of comparable monitors.
• They have a dynamic contrast ratio of up to 1,000,000:1.
• LED based monitors are the latest technology and offer HD quality resolution.

OLED Monitors

• (Organic Light Emitting Diodes (OLED)) is a flat light emitting technology, made by placing a series of organic thin films between two conductors.
• A bright light is emitted when electrical current is applied.
• OLEDs are emissive displays.
• They do not require a backlight and so are thinner and more efficient than LCD displays (which require a white backlight).

OLED Display

• OLEDs are extremely thin.
• They can also be made transparent, flexible, foldable and even rollable and stretchable in the future.
• OLEDs are 30% more expensive than LEDs
• OLEDs have limited lifetime.
• OLEDs can be problematic in direct sunlight.
• Water can be a real killer.
• Other Advantages include a better picture quality, more power efficiency/thickness.
• The have a response time of 100 kHz (100,000 Hz)!!

Pixels

• The Resolution of every screen is measured by the number of pixels it shows.
• It is always written in Width x Height and can be used as measurement for digital photos and videos.
• A pixel (or picture element) is the smallest item of information in an image.

Test your knowledge of computer hardware. This quiz covers topics, such as storage units, CPU, RAM, and data transfer. Sharpen your understanding of fundamental computer components.