System Hardware. FPU – Floating Point Unit Handles floating point and extended integer calculations 8284/82C284 Clock Generator (clock) Synchronizes the CPU and the rest of the computer 8259 Programmable Interrupt Controller (PIC)
EA: Effective address – the time it takes for the processor to calculate various addressing modes.
(EA calculation is NOT a factor from the 286 onward. It is done at the hardware level, so there is no difference in execution speed between a direct operand and a base-indexed operand).
Example – For a 33MHz 386 processor:
(2 clock cycles for INC instruction)/33000000)
= 0.00000006 sec (60nsec)
Note: This does not take into consideration parallel execution of instructions.