• Back in the days of Windows 95, the Intel Pentium II processors were the fastest workhorses around. With speeds ranging from 233 megahertz (Mhz) up to 450 Mhz, these processors were marketed to professionals, personal computer enthusiasts and power users. While puny by today's standards of extreme processor speed, the Pentium II represented great strides in technology, far surpassing the competition. Many older computers still running today operate on Pentium II processors, which testifies to the power and longevity of the chip.
  
  

Pentium II 233 Mhz and 266 Mhz

• The slowest processors in the Pentium II family, these chips have a 512 kilobyte (KB) cache and a 66 Mhz front-side bus speed. Commonly used in lower-end consumer desktops, the processors differ only by marginal clock speeds considered insignificant today.
  
  

Pentium II 300 Mhz and 333 Mhz

• Marketed to computer users that needed more power, these second-tier processors didn't need the firepower of the flagship processors. The desktops these processors were found within were geared towards amateurs that fancied themselves power users or those that worked heavily on the computer using simple programs and wanted a more responsive machine. The processors have a 512 KB cache and a 66 Mhz front-side bus. Additionally, the core-to-bus ratio, which measures the amount of processing cores to the amount of communication channels, is slightly higher than the 200 Mhz range processors.
  
  

Pentium II 350 Mhz, 400 Mhz and 450 Mhz

• These three processors represent the best of the Pentium II line. Intended for graphic design and picture editor professionals, these users needed every ounce of processing power they could get for their graphic needs. These power users needed high speeds for processor-heavy activities and Intel accommodated them with this processor. All three processors have a 100 Mhz front-side bus, which leads to markedly-increased processor speeds over a chip with the same clock speed but a lower front-side bus speed. While the cache is still set at 512 KB, the bus-to-core ratios are 3.5, 4.0 and 4.5 respectively, compared to 3.0 in the low-end series and 3.5 in the mid-range series.
  
  

Intel Pro

• The original Pentium II processor, the Pro is a lower-end chip. It differs from other chips in its connection -- rather than a slot-1 connection, it uses socket-8, which is a flat form factor. The processor has a clock speed of 200 Mhz, with a front-side bus of 66 Mhz.
  
  

Intel Celeron

• The processor is the budget chip in the Pentium II line. Intended for low-end, inexpensive desktops, the processor clocks in at 233 Mhz and does not have an "L2" cache. This causes the processor to run considerably slower than those with caches, as all information must be written directly to the slower system memory.
  
  

Pentium II Xeon

• Similar to the high-end processors listed above, the Xeon was used in servers and work stations. Its cache was huge for its time, using a full two megabytes of memory. This led to extremely fast processing speeds necessary for the high loads with which servers regularly deal. Clock speeds ran from 350 Mhz to 450 Mhz.
  
  

Mobile Pentium II

• Only laptops used the Mobile Pentium II. Due to the limited power supply that laptops have, the processor clocks in at a relatively low 233 Mhz with a 512 KB cache. While the processor speed is slow, the large cache helps to compensate for it.