The ALU carries out calculations and
makes decisions on the data sent to the
processor. This is where the computer
processes data either by manipulating it or
acting upon it. It consists of two parts.
Arithmetic part- Which does exactly
what you think it should- It performs the
calculation on the data.
Logic part- This deals with logic and
comparisons. For example, it works out if one
value is greater, less than or equal to another.
Control unit (CU
Registers
MAR
MDR
Program Counter
Accumulator
Factors that affect the performance of the
CPU
Number of cores
Single core
Quad core
Dual core
Type of processor
CISC
RISC
Clock Speed
Fetch, Decode, Execute
Fetch
Data is fetched from the MDR register
It is quicker to access data stored in the
registers than to access main memory RAM
BUT... If the data is not in main
memory it needs to request data
from secondary storage which is
much slower