Transcript Computer Hardware & Processing – Part 2

Computer Hardware & Processing
Inside the Box
CSC 101
1.0
September 16, 2010
Why does computer technology change so quickly
Moore’s law
Technology changes every 18 months
The Motherboard
• CPU
• RAM
• Expansion
cards and
slots
• Built-in
components
The CPU - Central Processing Unit
• Referred to as the “brains” of the
computer
• Controls all functions of the
computer
• Processes all commands and
instructions
• Can perform billions of tasks per
second
How fast is a CPU?
• Speed
– Megahertz (MHz)
– Gigahertz (GHz)
– System clock
• Cores
– Single
– Dual
– Quad
Parts of the CPU
The Machine Cycle
Computer Memory
• RAM – Random Access Memory
• ROM – Read Only Memory
• Cache Memory – very fast memory used by
the CPU
ROM
• Hard wired at
the factory
• Cannot be
changed
• Contains the
instructions the
computer
needs to start
RAM
• Volatile – No power, no data
• All programs and files must be loaded into
RAM to be used
• RAM connected to the CPU
• Primary storage
How much RAM do you need?
It depends on what programs you run
Operating system is always in RAM
Application
Minimum RAM Required
Windows 7
1000 MB
Microsoft Office Professional 2007
256 MB
Internet Explorer 8
128 MB
iTunes
256 MB
Adobe Photoshop Elements
512 MB
Total RAM required to run all programs
2,152 MB or 2.15 GB
simultaneously
Virtual Memory
• Space reserved on the hard drive
• Computer act like it has more memory than it
really has
• Programs swapped between real memory and
virtual memory as needed
• Thrashing – computer spends too much time
swapping between real and virtual memory
Cache Memory & Registers
• Very fast memory
• On the CPU chip or
in very close
proximity
• Holds processors
immediate results
• Holds frequently
used instructions
Device/Memory/Storage Hierarchy
The higher in the hierarchy, the faster and more expensive memory is
Expansion Slots
• Adds versatility and expandability to the
system
Video Cards
• Process binary data into images
• Contain memory known as video memory
• Control the number of colors a monitor can
display (bit depth)
– Standard VGA
– True color
Graphics Processing Unit
• Performs the same work as a CPU
• Specialized to handle
– 3D graphics
– Image and video processing
• CPUs perform better with a GPU handling
graphics computation.
Audio Processing
• Sound cards
– Attach to
motherboard
– Process digital data
into sounds
– 3D sound cards
– Surround sound
– Allow you to connect
audio devices
Bus
• Move bits between different areas on the
motherboard
• 32 bit
• 64 bit
Ports
• Allow peripheral
devices to be
plugged in
• On both front
and back of
desktop
computers
– USB
– Ethernet
– Firewire