The Pentium Pro   

Introduced in the year 1995, the Pentium Pro reflected  still  more  design  breakthroughs.  The Pentium Pro may process 3 instructions in a single clock cycle- 1 more than the Pentium. In addition, the Pentium Pro may gain faster clock speeds-the earliest model available was packaged with a 133 MHz clock. Intel coined the phrase "dynamic execution" to explain the specific innovation that distinguishes the Pentium Pro. Dynamic execution refers to the ability of chip to execute program instructions in the most efficient manner, not necessarily in the order in which they were written. This out-of-order execution means that instructions that can't be executed instantaneously are put aside, while the Pentium Pro start processing other instructions.  In  contrast  this  is  to  the  original  Pentium  chip  that  may stall  because  it  executes instructions in strict sequence.