CPU Architecture

CPU Architecture

1. Cores

   • each core process data independently
   • more cores, more instructions can be processed
   • most computers have 4 cores

2. Clock

   • clock speed
     • the number of instructions per second a single prosessor core can carry out per second
       • E.g. 3.5 GHz (3.5 billion instructions per second)
     • higher the clock speed the greater number of instructions can be carried out per second
   • computers can be overclocked
     • damage or overheat systems
       • cooling systems e.g. water cooling

3. Cache

   • RAM
     • Secondary storage
       • Type of storage media
         • Solid state drive
           • Fast
           • Reliable
           • No moving parts
           • internal storage
           • Significantly faster read/write times than HDDs
           • Shock-proof
           • Silent
         • Optical
           • CDs
             • 700MB
           • DVDs
             • 4.7GB
           • Blu-Ray
             • 25GB
           • Optical discs come in three forms
             • read-only
               • E.g. CD-ROM/DVD-ROM/BD-ROM
             • write-only
               • E.g. CD-R/ DVD-R/ BD-R
             • rewritable
               • E.g.CD-RW/DVD-RW/BD-RW
           • use is declining
           • low capacity
           • very slow read/write times
           • Cheap
           • wont be damaged by water or shocks
             • although easily scratched
         • Magnetic
           • Hard Disk Drives
             • long lasting
             • Makes some noise
             • low cost compared to SSD
             • longer read and write times
           • high capacity storage
           • reliable
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       • non- volatile
       • read and write speeds are much slower
     • (random access memory)
     • Volatile
     • main memory
     • can be read or written
     • where data is stored when it is being used
     • when computer starts operating system is copied from secondary storage to RAM
     • faster the secondary storage
     • slower than cache
   • very fast memory in the CPU
     • faster than RAM
   • stores regularly used data
     • CPU can access it quickly
   • High cost
   • Low capacity

4. ROM

   • (read only memory)
   • non-volatile
   • can not be written
   • a chip built in to the motherboard
   • contains all the instuctions to boot up the computer
     • Basic Input Output System (BIOS)
   • tells the CPU to perform self checks and set up

5. (central processing unit )

6. "brain" of the computer

7. processes all data and instructions

8. The Arithmetic Logic Unit

   • ALU does all the calculations

9. The Control Unit

   • overall control
   • execute program instructions
     • Fetch > Decode > Excute