Inside a Computer
Using an air duster - do not press so hard that the components freeze!!
Parts of the example computer:
CPU - processes data and instructions
Motherboard - The board which holds a lot of the components
Graphics Card - generates what a user sees on a screen. Some users have more than one graphics card so that games/images/videos can be loaded/played a lot quicker. Can loads more frames per second.
Sounds Card -
Heat Sink -
ROM -
RAM - DIMMs (double impact memory modules) 2GB x 2 (266megahertz). Memory is usually paired (black slot AND white slot). Volatile - will only store things while the computer is on.
RAM - DIMMs (double impact memory modules) 2GB x 2 (266megahertz). Memory is usually paired (black slot AND white slot). Volatile - will only store things while the computer is on.
Hard Drive - Non volatile storage - will store things when computer is turned off. But is NOT ROM as you can read AND write to it
CD ROM -
USB Ports -
Data Buses - send the data to the ROM
Power supply -
BIOS - tells
FireWire Ports - old school!
SATA cables - faster than IDE
PCI / PCIE -
Example: You are typing a letter in Word. Your computer stores this as a temporary file using the RAM. When you hit save this saves to the hard drive.
OUR TASK: What is the average RAM speed and size?
OUR RESEARCH:
Current PCs range from 2GB-16GB
The more RAM your computer holds the more programs it can handle simultaneously
DDR3 is faster than DDR2
SDRAM - 66Mhz, 100Mhz, 133Mhz
DDR1 - 266Mhz, 333Mhz, 400Mhz
DDR2 - 400Mhz, 533Mhz, 677Mhz, 800Mhz
DDR3 - 400Mhz, 533Mhz, 677Mhz, 800Mhz, 933Mhz, 1066Mhz
DDR4.... etc.....
Memory speed - Mhz
Memory size - GB
Gaming/Video editing PC - 32GB - 2133Mhz
Desktop PC - 8GB - 1600Mhz
Laptop PC - 8GB - 1600Mhz
4GB/666Mhz is the average currently
CPU:
High end - 2.3Ghz - 16 cores - £3700
Average - 2.6Ghz - 4 cores - £10
NB: Processors can overheat if they have no cooling fan! Go to YouTube and search for “CPU fire”!!
Moore’s Law - storage and memory will keep doubling
Buses:
Connects one part of the motherboard to another
FSB - connects the CPU to the north bridge
Bus speed* average range: 80-400Mhz
Bus speed - speed everything travels around the motherboard
Analogy - A slow bus will stop everywhere! A fast bus will get you to your destination quickly!
Hard drive:
Average physical size: 3.5inch desktops
6 metal discs one on top of each other - ICTWorkout.co.uk
Average memory size: Around 500GB-1TB
Largest hard drive found: 16TB - £5000
SSD - Solid State Disc - No moving parts - faster
7200RPM - 100MB per second
RAM is 20x faster than the hard drive at getting data
RAID -
Graphics Card:
Built into the motherboard - do not need to buy another unless you want more video RAM for instance, or more memory for gaming
Average size is 8GB
Fetch - Execute - Decode:
Registers:
- PC - Program Counter
- MAR - Memory Address Register - where I am currently looking
- MDR - Memory Data Register - the MAR loads data into this
- CIR - Control Instruction Register
Control Unit - looks up the load command
Memory - where data is stored
AC - Accumulator - where it stores the data (essentially RAM)
ALU (bit that does the maths) - adds the numbers together and replaced them with the answer
*use fetchexecute.swf to show this process using an animation