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                  From 486CPU To Pentium Processor
   What makes a Pentium Processor run significantly faster than a 
486CPU ? The Pentium Processor family has significant improvements 
over the Intel486CPU,here are some of them:
   A superscalar architecture capable of executing two integer instructions 
in parallel in a single clock, achieving up to two times the integer
performance relative to an equivalent frequency Intel486CPU.
   The 64-bit data bus doubles the speed at which information is carried 
between the processor and memory subsystem.
   An extended form of paging provides access to data structures larger 
than the available memory space by keeping them partly in memory and 
partly on disk.
   Separate internal code and data caches improve performance by reducing 
average memory access time and providing fast access to recently-used 
instructions and data. The instruction and data caches can be accessed 
simultaneously. The data cache supports a write-back (or alternatively 
write-through) policy for memory updates.
   Dynamic branch prediction uses the Branch Target Buffer (BTB) to 
boost performance by predicting the most likely set of instructions to 
be executed.
   A pipelined Floating-Point Unit (FPU) for supporting the 32-bit and 
64-bit formats specified in IEEE standard 754, as well as an 80-bit 
format. It is capable of executing two floating-point instructions in 
a single clock. The FPU is object-code compatible with the Intel486DX 
and Intel487SX, Intel387DX, and Intel387SX math-coprocessors.
   Bus control signals for maintaining cache consistency in multiprocessor 
systems.
   Multiprocessor interrupt controller on-chip, enabling low-cost 
symmetric multiprocessing. 
   Hardware support for virtual interrupts provided through the "Virtual 
Interrupt Flag (VIF) "and "Virtual Interrupt Pending ".
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