Hardware Reference
In-Depth Information
For more information about the Pentium II, see Chapter 3 of
Upgrading and Repairing PCs
, 19
th
Edition, available in its entirety on the disc packaged with this topic.
Pentium III
The Pentium III processor, shown in
Figure 3.30
,
was released in February 1999 and introduced
several new features to the P6 family. It is essentially the same core as a Pentium II with the addition
of SSE instructions and integrated on-die L2 cache in the later versions. SSE consists of 70 new
instructions that dramatically enhance the performance and possibilities of advanced imaging, 3D,
streaming audio, video, and speech-recognition applications.
Figure 3.30. Pentium III processor in SECC2 (Slot 1) and FC-PGA (Socket 370) packages.
Originally based on Intel's advanced 0.25-micron CMOS process technology, the PIII core started out
with more than 9.5 million transistors. In late 1999, Intel shifted to a 0.18-micron process die (code-
named Coppermine) and added 256KB of on-die L2 cache, which brought the transistor count to 28.1
million. The last version of the Pentium III (code-named Tualatin) uses a 0.13-micron process and
has 44 million transistors; motherboards made before the Tualatin-core versions of the Pentium III
generally do not support this processor because of logical pinout changes. The Pentium III was
manufactured in speeds from 450MHz through 1.4GHz, as well as in server versions with larger or
faster cache known as the Pentium Xeon. The Pentium III also incorporates advanced features such as
a 32KB L1 cache and either half-core speed 512KB L2 cache or full-core speed on-die 256KB or
512KB L2 with cacheability for up to 4GB of addressable memory space. The PIII also can be used
in dual-processing systems with up to 64GB of physical memory. A self-reportable processor serial
number gives security, authentication, and system management applications a powerful new tool for
identifying individual systems. Because of privacy concerns when the processor was released, you
can disable this feature in the system BIOS on most systems that use the Pentium III or Celeron III
processors.
Pentium III processors were made available in Intel's SECC2 form factor, which replaced the more
expensive older SECC packaging. The SECC2 package covers only one side of the chip and allows
for better heatsink attachment and less overall weight. Architectural features of the Pentium III
processor include the following:
•
Streaming SIMD extensions (SSE)
—Seventy new instructions for dramatically faster
processing and improved imaging, 3D streaming audio and video, web access, speech
recognition, new user interfaces, and other graphics and sound-rich applications.
•
Intel processor serial number
—Serves as an electronic serial number for the processor and,
