Next Saturday, March 22, a mere 11 days from now, the Intel Pentium processor will turn a grand 15 years of age. The Pentium marked a pretty dramatic increase in x86-based processor optimization capabilities, namely the introduction of multiple instruction pipelines. The optimization gains were so much so, that many software packages don’t usually enable CPU code optimization beyond the standard 386-level 32 bit code until you get to the Pentium/i586 architecture.

The age of the Pentium CPU was quite astonishing for me to realize. I remember our family purchasing our first Intel-based PC in 1993 with a 486 CPU. At the time, the Pentium was brand new. Those who were involved in the computer industry during this transition to brave new CPU-worlds will remember that the original Pentium chips, running at a blazing 60 and 66 MHz, had numerous heat issues. The 486 and earlier CPUs of the time did not have the heat dissipation issues that the Pentium chips had, so the older CPUs could usually get by with merely a heat sink attached to the chip. The Pentium was the first real introduction to computer enthusiasts of the requirement for not only a heat sink for the CPU, but a fan for active cooling of that heat sink as well.

Continuing in our early-to-mid-nineties throwbacks, the Pentium Pro will turn 13 in November of this year, reaching CPU adolescence. The Pentium Pro itself may not have seen wide adoption among computer enthusiasts, who instead opted to upgrade to the more consumer-friendly Pentium IIs, but the Pentium Pro left us quite a legacy of its own. The Pentium Pro ushered in the i686 instruction set, the prevailing 32 bit x86 instruction set to this day. The x86 instruction set would not see another serious upgrade until the release of the first x86_64 instruction set-based CPU, the AMD Opteron, in 2003. It would be approximately a year later before the first Intel CPUs sporting the new 64 bit architecture began shipping. It’s still amazing to me that the i686 instruction set, still the most widely used instruction set for x86 machines, is almost 13 years old. Around the time that Pentium Pro arrived on the scene, RISC architecture was becoming more and more prevalent, and the industry buzz was that RISC would become the architecture of choice, even for desktop CPUs. With the increasing optimization of the x86 architecture, including the inclusion of several RISC principles in the CPU, the i686 instruction set has lived on, and pure RISC has all but become a thing of the past, relegated to niche sectors of the computing world. Of course, the most recent, and high profile, casualty of this is the switch Apple, Inc. made during the 2006 year from its previous PowerPC based machines to its current Intel-based machines.

The first real usage of a brand for CPUs by Intel, the Pentium name is still with us to this day. With the introduction of the newer Core branding from Intel, the Pentium name has taken its place as the new moniker for lower-end processors from the silicon giant. Still, its been a great 15 years. Here’s lookin’ at you, kid.