TOPIC 1 - Hardware, Processor, Memory Flashcards
Why is understanding IT important?
You will make better decisions if you understand the options and their tradeoffs
social engineering
when hackers use their knowledge of psychology to trick people in divulging confidential information
what are hardware components
basic components of a computer
name the 6 types of hardware components
processor, main memory, secondary storage, input devices, output devices, communication devices
processor definition
central processing unit where symbols, characters, and numbers are manipulated
main memory defintion
where data and program instructions are stored temporarily during the process
secondary storage
stores data and programs even when the computer is turned off
input devices definition
convert data and instructions from the outside world into the electronic form suitable for the computer
examples of input devices
keyboard, mouse, touchpad, touchscreen, mic, camera
output device definition
converts electronic data produced by the computer into a form understood by humans or the outside world
examples of output devices
monitor, speaker, printer
communication devices definition
provide connections between the computer and communication networks
examples of communication devices
network interface card, ethernet, wifi, bluetooth
Small b vs big B
How many different values?
small b is for bit -> 2 possible values
big B is for byte (8 bits)-> 256 possible values
data storage and data transfers refer to which multiples?
1024 (K,M,G,T)
metric system or frequencies refer to which multiples?
multiples of 1000
How many bytes are in a KB?
1024
What is bandwidth and how is it measured?
bandwidth refers to speed and is measured in bits per second.
What is word size?
a measure of how many bits a processor can transfer/manipulate at the same time
what are the 2 different word size architectures and where are they used?
32 bit: older and inexpensive smartphones
64 bit: premium smartphones, recent laptops and servers
what is backwards compatibility?
the new version of one component is designed to work with remaining older components
Processors are built for 2 reasons. Name the reasons.
Built for efficiency and built for speed
Name the characteristics of a processor built for efficiency.
- run for a long time with a small battery
- no fan
- minimize transistors
- smartphones and tablets
Name the characteristics of a processor build for speed
- large battery or plug in
- need a fan
- complex with many transistors
- used in laptops, desktops, and servers
Role of the processor in a computer
processor is the part that does computation and only executes simple instructions
goal of simple instructions and examples
to be executed very quickly
- arithmetic and logic
- comparisons
- accessing data
- flow control
Name the components of a processor
program counter, instruction register, arithmetic logic unit, registers, control unit, cache
define the program counter and where it is located
located in the processor, it holds the address of the current or next instruction
define the instruction register and where it is located
located in the processor, holds the instruction that is being/about to be executed
define the arithmetic logic unit and where it is located
located in the processor, performs arithmetic and logic operations
define the registers and where it is located
located in the processor, is a small amount of temporary and fast storage - usually a source/destination for the data
define the control unit and where it is located
located in the processor, reads the instruction in the IR and turns on/off the other components of the processor to execute instruction
define the cache and where it is located
located in the processor, and stores recently used data and instructions
the speed at which you can access memory depends on?
depends on the size of the memory, the smaller = the faster.
Implication of more cache levels
The more levels of cache the better - it is faster but more expensive
Which level would store frequent data & instructions?
smallest cache and can be accessed quickly
Define a multicore processor and the 2 most common
each core acts like a separate processor on the same chip.
- duo core: 2 cores and 2 instructions at the same time
- quad-core: 4 cores and 4 instructions at the same time
How is processor power/performance measured?
typically reported as clock speed (frequency)
processing power is based on what 4 aspects?
- number of cores
- word size
- bus speed
- complexity of instruction
the speed a clock ticks is measured in:
MHz: 1 million clock ticks per second
GHz: 1 billion clock ticks per second
types of storage devices (5)
- static random access memory
- dynamic random access memory
- solid state drive
- hard drive
- usb flash drive
why not have one type of storage device?
gap between processor performance and memory performance. performance has been increasing much faster - accessing memory is the bottleneck
state the memory hierarchy
registers caches RAM solid state drive hard drive network storage off site storage (cloud)
top of memory hierarchy characteristics
fastest, most expensive, smallest capacity, closest
bottom of memory hierarchy characteristics
slowest, least expensive, largest capacity, farthest away
compare and constrast the 2 types of random access memory
static ram: expensive but faster and is used for registers
dynamic ram: less expensive but slower, used for RAM
goal of memory hierarchy
store commonly used data & instructions in fast memory and rarely used data and instructions in slow memory
what are the 2 main types of memory
main memory and secondary storage
name the 3 components of main memory and their characteristics
components: registers, caches, RAM (load programs/files into RAM from secondary storage to access)
characteristics: faster, expensive, volatile
what does main memory store?
- All of part of the software program being executed
- The data that the program is using
- The operating system programs that manage the operation of the computer
name the different types of secondary storage and characterisitcs?
types: hard drive, flash drive, optical drive
characteristics: slower, cheaper, non-volatile
secondary storage is also referred to as:
external memory/storage because it is not directly accessible by the processor
data and programs must be copied to main memory for access
name the parts of a hard drive
- main PCB
- ribbon cable
- actuator
- actuator axis
- actuator arm
- read/write head
- spindle
- platter
what is a platter?
set of disks stacked on top of each other each with magnetic coating on both sides
what is RPM?
how fast the disk is spinning, rotations per minute, higher RPM= faster access
what is an actuator arm?
moves across the disk to position the read/write heads
what does the read/write head do?
Read/write head changes the orientation of the magnetic field at a particular location to represent 0 or 1
what curve does mean time between failures follow?
bathtub curve, more likely to fail initially due to manufacturing error and later failure due to wearing out
pros of a solid state drive
- 10x faster to access data
- Lasts longer
- No moving parts that can wear out
cons of a solid state drive
- More expensive
- Wear out sooner than a hard disk drive when writing a lot of data
- Data can fade over time
Discuss when adding RAM would/would not improve computer performance
improve: if there is not enough RAM, OS will use secondary storage which is much slower and will degrade performance
not improve: when there is enough RAM
