Intel made some major changes to the processor scene with the release of the Pentium II. They had the PentiumMMX and Pentium Pro’s out into the market in a strong way, and they wanted to bring the best of both into one chip. As a result, the Pentium II is kind of like the child of a Pentium MMX mother and the Pentium Pro Father. But like real life, it doesn’t necessarily combine the best of it’s parents. Pentium II is optimized for 32-bit applications. It also contains the MMX instruction set, which is almost a standard by this time. The chip uses the dynamic execution technology of the Pentium Pro, allowing the processor to predict coming instructions, accelerating work flow. It actually analyzes program instruction and re-orders the schedule of instructions into an order that can be run the quickest. Pentium II has 32KB of L1 cache (16KB each for data and instructions) and has a 512KB of L2 cache on package. The L2 cache runs at ½ the speed of the processor, not at full speed. Nonetheless, the fact that the L2 cache is not on the motherboard, but instead in the chip itself, boosts performance.

This is a list of Pentium II specs, as provided by Intel:

• Available in speeds from 233 MHz up to 450 MHz.
  
• Utilizes Intel’s 0.25 micron manufacturing process for increased processor core frequencies and reduced power consumption.
  
• Includes MMX media enhancement technology.
  
• The Pentium(r) II processor at 450 MHz delivers 32% more integer performance (as measured by SPECint95), 30% more multimedia performance (as measured by Norton Media Benchmark), and 35% more floating point performance (as measured by SPECfp95) than the 333 MHz Pentium(r) II processor.
  
• Dual Independent Bus (DIB) architecture increases bandwidth and performance over single-bus processors.
  
• 450, 400, and 350 MHz versions improve system bandwidth and performance by increasing the system bus speed from 66 MHz to 100 MHz. The Intel® 440BX AGP set enables the 100 MHz system bus to increase peak processor data transfers to the rest of the system by 50%.
  
• Single Edge Contact (SEC) cartridge packaging technology delivers high-performance processing and bus technology to mainstream systems.
  
• 32K (16K/16K) non-blocking, level-one cache provides fast access to heavily used data.
  
• 512K unified, non-blocking, level-two cache.
  
• 450, 400, and 350 MHz versions support memory cacheability for up to 4GB of addressable memory space.
  
• Enables scalable systems to be expanded to two processors and 64GB of physical memory.
  
• Includes data integrity and reliability features such as Error Correction Code (ECC), Fault Analysis, Recovery, and Functional Redundancy Checking for both system and L2 cache buses.

One of the most noticeable changes in this processor is the change in the package style. Almost all of the Pentium class processors use the Socket 7 interface to the motherboard. Pentium Pro’s use Socket 8. Pentium II, however, makes use of “Slot 1″. The package-type of the P2 is called Single-Edge contact (SEC). The chip and L2 cache actually reside on a card which attaches to the motherboard via a slot, much like an expansion card. The entire P2 package is surrounded by a plastic cartridge. In addition to Intel’s departure into Slot 1, they also patented the new Slot 1 interface, effectively barring the competition from making competitor chips to use the new Slot 1 motherboards. This move, no doubt, demonstrates why Intel moved away from Socket 7 to begin with - they couldn’t patent it.

The original Pentium II was code-named “Klamath”. It ran at a paltry 66 MHz bus speed and ranged from 233MHz to 300MHz. In 1998, Intel did some slight re-working of the processor and released “Deschutes”. They used a 0.25 micron design technology for this one, and allowed a 100MHz system bus. The L2 cache was still separate from the actual processor core and still ran at only half speed. They would not rectify this issue until the release of the Celeron A and Pentium III. Deschutes ran from 333MHz to up to 450 MHz.