Pentium III

Pentium III. The Pentium III is a x86 microprocessor introduced by Intel in February 1999 as the successor to the Pentium II. It was designed to enhance performance for demanding applications like 3D graphics, streaming media, and voice recognition. The processor family was notable for introducing the SSE instruction set and became a mainstream choice for both consumer and business desktop computers and workstations throughout its production life.

Overview

The launch of the processor represented a significant evolution in Intel's product line, building upon the established P6 microarchitecture. Initial models were released for the Slot 1 interface, maintaining compatibility with existing motherboard platforms. A key marketing and technical focus was on improving performance for emerging internet and multimedia applications, which were rapidly gaining popularity. The brand was positioned against competing products from Advanced Micro Devices, notably the Athlon processor.

Architecture

The core architecture was based on the P6 microarchitecture, sharing fundamental design principles with the Pentium Pro and Pentium II. A major architectural addition was the SSE instruction set, which added 70 new instructions for accelerating floating-point and parallel data processing. The processor featured an integrated L2 cache, though its speed and integration method evolved across different models. Other enhancements included an improved branch prediction unit and a faster system bus compared to later Pentium II models, improving data throughput with the chipset.

Models and variants

The product line was segmented into several distinct models targeting different market segments. The initial Katmai core, manufactured on a 0.25 µm process, featured 512 KB of external L2 cache running at half core speed. The subsequent Coppermine core, using a 0.18 µm process, integrated the L2 cache directly onto the die and introduced the FC-PGA package for Socket 370. The final Tualatin core, also on a 0.13 µm process, offered enhanced performance and lower power consumption, though it was largely relegated to the server and mobile computing markets. A lower-cost derivative, the Celeron, was also based on these cores.

Performance and reception

Upon release, the processor was generally well-received for its strong performance in business and consumer applications, particularly those optimized for SSE. In professional reviews, it often demonstrated a lead over the AMD K6-III but faced intense competition from the subsequently released AMD Athlon. Its performance in Quake III Arena and other 3D games was a common benchmark. The transition to the Coppermine core was praised for delivering significant clock speed increases and efficiency gains, helping Intel remain competitive in the high-performance desktop market.

Security features and controversies

A significant and controversial feature introduced with the initial Katmai core was the Processor Serial Number, a unique identifier intended to enhance security for e-commerce transactions. This feature sparked major privacy concerns from advocacy groups like the Electronic Frontier Foundation and led to public backlash, prompting Intel to provide software disable options. Furthermore, the processor was involved in several patent disputes, including a notable case with Intergraph Corporation concerning Clipper technology. These issues, however, did not substantially impact its widespread adoption in OEM systems from major manufacturers like Dell and Compaq. Category:Intel microprocessors Category:x86 microprocessors