|Launched||February 26, 1999|
|Discontinued||May 18, 2007|
|Max. CPU clock rate||400 MHz to 1.4 GHz|
|FSB speeds||100 MHz to 133 MHz|
|Architecture and classification|
|Min. feature size||0.25 μm to 0.13 μm|
|Instruction set||IA-32, MMX, SSE|
|Products, models, variants|
|Successor||Pentium 4, Xeon, Celeron, Pentium M|
The Pentium III(marketed as Intel Pentium III Processor, informally PIII or P3, and stylized as pentium !!!) brand refers to Intel's 32-bit x86 desktop and mobile microprocessors based on the sixth-generation P6 microarchitecture introduced on February 26, 1999. The brand's initial processors were very similar to the earlier Pentium II-branded microprocessors. The most notable differences were the addition of the Streaming SIMD Extensions (SSE) instruction set (to accelerate floating point and parallel calculations), and the introduction of a controversial serial number embedded in the chip during manufacturing.
Even after the release of the Pentium 4 in late 2000, the Pentium III continued to be produced with new models introduced until early 2003, and were discontinued in April 2004 for desktop units,and May 2007 for mobile units.
Similarly to the Pentium II it superseded, the Pentium III was also accompanied by the Celeron brand for lower-end versions, and the Xeon for high-end (server and workstation) derivatives. The Pentium III was eventually superseded by the Pentium 4, but its Tualatin core also served as the basis for the Pentium M CPUs, which used many ideas from the P6 microarchitecture. Subsequently, it was the Pentium M microarchitecture of Pentium M branded CPUs, and not the NetBurst found in Pentium 4 processors, that formed the basis for Intel's energy-efficient Core microarchitecture of CPUs branded Core 2, Pentium Dual-Core, Celeron (Core), and Xeon.
|Intel Pentium III processor family|
|Standard Logo (1999-2003)||Mobile Logo (1999-2003)||Desktop|
|List of Intel Pentium III microprocessors|
The first Pentium III variant was the Katmai (Intel product code 80525). It was a further development of the Deschutes Pentium II. The Pentium III saw an increase of 2 million transistors over the Pentium II. The differences were the addition of execution units and SSE instruction support, and an improved L1 cache controller[ citation needed ] (the L2 cache controller was left unchanged, as it would be fully redesigned for Coppermine anyway), which were responsible for the minor performance improvements over the "Deschutes" Pentium IIs. It was first released at speeds of 450 and 500 MHz in February 1999. Two more versions were released: 550 MHz on May 17, 1999 and 600 MHz on August 2, 1999. On September 27, 1999 Intel released the 533B and 600B running at 533 & 600 MHz respectively. The 'B' suffix indicated that it featured a 133 MHz FSB, instead of the 100 MHz FSB of prior models.
The Katmai contains 9.5 million transistors, not including the 512 Kbytes L2 cache (which adds 25 million transistors), and has dimensions of 12.3 mm by 10.4 mm (128 mm2). It is fabricated in Intel's P856.5 process, a 0.25 micrometre complementary metal–oxide–semiconductor (CMOS) process with five levels of aluminum interconnect. The Katmai used the same slot-based design as the Pentium II but with the newer Slot 1 Single Edge Contact Cartridge (SECC) 2 that allowed direct CPU core contact with the heat sink. There have been some early models of the Pentium III with 450 and 500 MHz packaged in an older SECC cartridge intended for original equipment manufacturers (OEMs).
A notable stepping level for enthusiasts was SL35D. This version of Katmai was officially rated for 450 MHz, but often contained cache chips for the 600 MHz model and thus usually can run at 600 MHz.
The second version, codenamed Coppermine (Intel product code: 80526), was released on October 25, 1999, running at 500, 533, 550, 600, 650, 667, 700, and 733 MHz. From December 1999 to May 2000, Intel released Pentium IIIs running at speeds of 750, 800, 850, 866, 900, 933 and 1000 MHz (1 GHz). Both 100 MHz FSB and 133 MHz FSB models were made. For models that were already available with the same frequency, an "E" was appended to the model name to indicate cores using the new 0.18 μm fabrication process. An additional "B" was later appended to designate 133 MHz FSB models, resulting in an "EB" suffix. In overall performance, Coppermine had a small advantage over the Advanced Micro Devices (AMD) Athlons it was released against, which was reversed when AMD applied their own die shrink and added an on-die L2 cache to the Athlon. Athlon held the advantage in floating-point intensive code, while the Coppermine could perform better when SSE optimizations were used, but in practical terms there was little difference in how the two chips performed, clock-for-clock. However, AMD were able to clock the Athlon higher, reaching speeds of 1.2 GHz before the launch of the Pentium 4.
In performance, Coppermine arguably marked a bigger step than Katmai by introducing an on-chip L2 cache, which Intel names Advanced Transfer Cache (ATC). The ATC operates at the core clock rate and has a capacity of 256 KB, twice that of the on-chip cache formerly on Mendocino Celerons. It is eight-way set-associative and is accessed via a Double Quad Word Wide 256-bit bus, four times as wide as Katmai's. Further, latency was dropped to a quarter compared to Katmai. Another marketing term by Intel was Advanced System Buffering, which encompassed improvements to better take advantage of a 133 MHz system bus. These include 6 fill buffers (vs. 4 on Katmai), 8 bus queue entries (vs. 4 on Katmai) and 4 write-back buffers (vs. 1 on Katmai). Under competitive pressure from the AMD Athlon, Intel reworked the internals, finally removing some well-known pipeline stalls.[ citation needed ] As a result, applications affected by the stalls ran faster on Coppermine by up to 30%.[ citation needed ] The Coppermine contained 29 million transistors and was fabricated in a 0.18 μm process.
Although its codename could give the impression that it used copper interconnects, its interconnects were aluminium. The Coppermine was available in 370-pin FC-PGA or FC-PGA2 for use with Socket 370, or in SECC2 for Slot 1 (all speeds except 900 and 1100). FC-PGA and Slot 1 Coppermine CPUs have an exposed die, however most higher frequency SKUs starting with the 866 MHz model were also produced in FC-PGA2 variants that feature an integrated heat spreader (IHS). This in itself did not improve thermal conductivity, since it added another layer of metal and thermal paste between the die and the heatsink, but it greatly assisted in holding the heatsink flat against the die. Earlier Coppermines without the IHS made heatsink mounting challenging. If the heatsink was not situated flat against the die, heat transfer efficiency was greatly reduced. Some heatsink manufacturers began providing pads on their products, similar to what AMD did with the "Thunderbird" Athlon to ensure that the heatsink was mounted flatly. The enthusiast community went so far as to create shims to assist in maintaining a flat interface.
A 1.13 GHz version (S-Spec SL4HH) was released in mid-2000 but famously recalled after a collaboration between HardOCP and Tom's Hardware GHz speed without various tweaks to the processor's microcode, effective cooling, higher voltage (1.75 V vs. 1.65 V), and specifically validated platforms. Intel only officially supported the processor on its own VC820 i820-based motherboard, but even this motherboard displayed instability in the independent tests of the hardware review sites. In benchmarks that were stable, performance was shown to be sub-par, with the 1.13 GHz CPU equalling a 1.0 GHz model. Tom's Hardware attributed this performance deficit to relaxed tuning of the CPU and motherboard to improve stability. Intel needed at least six months to resolve the problems using a new cD0 stepping and re-released 1.1 GHz and 1.13 GHz versions in 2001.discovered various instabilities with the operation of the new CPU speed grade. The Coppermine core was unable to reliably reach the 1.13
Microsoft's Xbox game console uses a variant of the Pentium III/Mobile Celeron family in a Micro-PGA2 form factor. The sSpec designator of the chips is SL5Sx, which makes it more similar to the Mobile Celeron Coppermine-128 processor. It shares with the Coppermine-128 Celeron its 128 KB L2 cache, and 180 nm process technology, but keeps the 8-way cache associativity from the Pentium III.
This revision is an intermediate step between Coppermine and Tualatin, with support for lower-voltage system logic present on the latter but core power within previously defined voltage specs of the former so it could work in older system boards.
Intel used the latest FC-PGA2 Coppermines with the cD0 stepping and modified them so that they worked with low voltage system bus operation at 1.25 V AGTL as well as normal 1.5 V AGTL+ signal levels, and would auto detect differential or single-ended clocking. This modification made them compatible to the latest generation Socket 370 boards supporting Tualatin CPUs while maintaining compatibility with older Socket 370 boards. The Coppermine-T also had two way symmetrical multiprocessing capabilities, but only in Tualatin boards.
They can be distinguished from Tualatin processors by their part numbers, which include the digits "80533", e.g. the 1133 MHz SL5QK P/N is RK80533PZ006256, while the 1000 MHz SL5QJ P/N is RK80533PZ001256.
The third revision, Tualatin (80530), was a trial for Intel's new 0.13 μm process. Tualatin-based Pentium IIIs were released during 2001 until early 2002 at speeds of 1.0, 1.13, 1.2, 1.26, 1.33 and 1.4 GHz. A basic shrink of Coppermine, no new features were added, except for added data prefetch logic similar to Pentium 4 and Athlon XP for potentially better use of the L2 cache, although its use compared to these newer CPUs is limited due to the relatively smaller FSB bandwidth (FSB was still kept at 133 MHz). Variants with 256 and 512 KB L2 cache were produced, the latter being dubbed Pentium III-S; this variant was mainly intended for low-power consumption servers and also exclusively featured SMP support within the Tualatin line.
Although the Socket 370 designation was kept, the use of 1.25 AGTL signaling in place of 1.5V AGTL+ rendered prior motherboards incompatible.This confusion carried over to the chipset naming, where only the B-stepping of the i815 chipset was compatible with Tualatin processors. A new VRM guideline was also designed by Intel, version 8.5, which required finer voltage steps and debuted load line Vcore (in place of fixed voltage regardless of current on 8.4). Some motherboard manufacturers would mark the change with blue sockets (instead of white), and were often also backwards compatible with Coppermine CPUs.
The Tualatin also formed the basis for the highly popular Pentium III-M mobile processor, which became Intel's front-line mobile chip (the Pentium 4 drew significantly more power, and so was not well-suited for this role) for the next two years. The chip offered a good balance between power consumption and performance, thus finding a place in both performance notebooks and the "thin and light" category.
The Tualatin-based Pentium III performed well in some applications compared to the fastest Willamette-based Pentium 4, and even the Thunderbird-based Athlons. Despite this, its appeal was limited due to the aforementioned incompatibility with existing systems, and Intel's only officially supported chipset for Tualatins, the i815, could only handle 512 MB RAM as opposed to 1 GB of registered RAM with the older, incompatible 440BX chipset. However, the enthusiast community found a way to run Tualatins on then-ubiquitous BX chipset based boards, although it was often a non-trivial task and required some degree of technical skills.
Tualatin-based Pentium III CPUs can usually be visually distinguished from Coppermine-based processors by the metal integrated heat-spreader (IHS) fixed on top of the package. However, the last models of Coppermine Pentium IIIs also featured the IHS — the integrated heat spreader is actually what distinguishes the FC-PGA2 package from the FC-PGA — both are for Socket 370 motherboards.
Before the addition of the heat spreader, it was sometimes difficult to install a heatsink on a Pentium III. One had to be careful not to put force on the core at an angle because doing so would cause the edges and corners of the core to crack and could destroy the CPU. It was also sometimes difficult to achieve a flat mating of the CPU and heatsink surfaces, a factor of critical importance to good heat transfer. This became increasingly challenging with the Socket 370 CPUs, compared with their Slot 1 predecessors, because of the force required to mount a socket-based cooler and the narrower, 2-sided mounting mechanism (Slot 1 featured 4-point mounting). As such, and because the 0.13 μm Tualatin had an even smaller core surface area than the 0.18 μm Coppermine, Intel installed the metal heatspreader on Tualatin and all future desktop processors.
The Tualatin core was named after the Tualatin Valley and Tualatin River in Oregon, where Intel has large manufacturing and design facilities.
Since Katmai was built in the same 0.25 µm process as Pentium II "Deschutes", it had to implement Streaming SIMD Extensions (SSE) using minimal silicon. To achieve this goal, Intel implemented the 128-bit architecture by double-cycling the existing 64-bit data paths and by merging the SIMD-FP multiplier unit with the x87 scalar FPU multiplier into a single unit. To utilize the existing 64-bit data paths, Katmai issues each SIMD-FP instruction as two μops. To compensate partially for implementing only half of SSE's architectural width, Katmai implements the SIMD-FP adder as a separate unit on the second dispatch port. This organization allows one half of a SIMD multiply and one half of an independent SIMD add to be issued together bringing the peak throughput back to four floating point operations per cycle — at least for code with an even distribution of multiplies and adds.
The issue was that Katmai's hardware-implementation contradicted the parallelism model implied by the SSE instruction-set. Programmers faced a code-scheduling dilemma: "Should the SSE-code be tuned for Katmai's limited execution resources, or should it be tuned for a future processor with more resources?" Katmai-specific SSE optimizations yielded the best possible performance from the Pentium III family but was suboptimal for Coppermine onwards as well as future Intel processors, such as the Pentium 4 and Core series.
The Pentium III was the first x86 CPU to include a unique, retrievable, identification number, called Processor Serial Number (PSN). A Pentium III's PSN can be read by software through the CPUID instruction if this feature has not been disabled through the BIOS.
On November 29, 1999, the Science and Technology Options Assessment (STOA) Panel of the European Parliament, following their report on electronic surveillance techniques asked parliamentary committee members to consider legal measures that would "prevent these chips from being installed in the computers of European citizens."
Intel eventually removed the PSN feature from Tualatin-based Pentium IIIs, and the feature was absent in Pentium 4 and Pentium M.
A largely equivalent feature, the Protected Processor Identification Number (PPIN) was later added to x86 CPUs with little public notice, starting with Intel's Ivy Bridge architecture and compatible Zen 2 AMD CPUs. It is implemented as a set of model-specific registers and is useful for machine check exception handling.
A new feature was added to the Pentium III: a hardware-based random number generator.It has been described as "several oscillators combine their outputs and that odd waveform is sampled asynchronously." These numbers, however, were only 32 bit, at a time when export controls were on 56 bits and higher, so they weren't state of the art.
Athlon is the brand name applied to a series of x86-compatible microprocessors designed and manufactured by Advanced Micro Devices (AMD). The original Athlon was the first seventh-generation x86 processor and was the first desktop processor to reach speeds of one gigahertz (GHz). It made its debut as AMD's high-end processor brand on June 23, 1999. Over the years AMD has used the Athlon name with the 64-bit Athlon 64 architecture, the Athlon II, and Accelerated Processing Unit (APU) chips targeting the Socket AM1 desktop SoC architecture, and Socket AM4 Zen microarchitecture. The modern Zen-based Athlon with a Radeon Graphics processor was introduced in 2019 as AMD's highest-performance entry-level processor.
Duron is a line of budget x86-compatible microprocessors manufactured by AMD. Released on June 19, 2000 as a lower-cost offering to complement AMD's then mainstream performance Athlon processor line, it also competed with rival chipmaker Intel's Pentium III and Celeron processor offerings. The Duron brand name was retired in 2004, succeeded by the Sempron line of processors as AMD's budget offering.
Celeron is a brand name given by Intel to a number of different low-end IA-32 and x86-64 computer microprocessor models targeted at low-cost personal computers.
Pentium 4 is a series of single-core CPUs for desktops, laptops and entry-level servers manufactured by Intel. The processors were shipped from November 20, 2000 until August 8, 2008. The production of Netburst processors was active from 2000 until May 21, 2010.
The Pentium II brand refers to Intel's sixth-generation microarchitecture ("P6") and x86-compatible microprocessors introduced on May 7, 1997. Containing 7.5 million transistors, the Pentium II featured an improved version of the first P6-generation core of the Pentium Pro, which contained 5.5 million transistors. However, its L2 cache subsystem was a downgrade when compared to the Pentium Pros.
The Athlon 64 is an eighth-generation, AMD64-architecture microprocessor produced by AMD, released on September 23, 2003. It is the third processor to bear the name Athlon, and the immediate successor to the Athlon XP. The second processor to implement the AMD64 architecture and the first 64-bit processor targeted at the average consumer, it was AMD's primary consumer microprocessor, and primarily competed with Intel's Pentium 4, especially the "Prescott" and "Cedar Mill" core revisions. It is AMD's first K8, eighth-generation processor core for desktop and mobile computers. Despite being natively 64-bit, the AMD64 architecture is backward-compatible with 32-bit x86 instructions. Athlon 64s have been produced for Socket 754, Socket 939, Socket 940 and Socket AM2. The line was succeeded by the dual-core Athlon 64 X2 and Athlon X2 lines.
The Pentium M is a family of mobile 32-bit single-core x86 microprocessors introduced in March 2003 and forming a part of the Intel Carmel notebook platform under the then new Centrino brand. The Pentium M processors had a maximum thermal design power (TDP) of 5–27 W depending on the model, and were intended for use in laptops. They evolved from the core of the last Pentium III–branded CPU by adding the front-side bus (FSB) interface of Pentium 4, an improved instruction decoding and issuing front end, improved branch prediction, SSE2 support, and a much larger cache. The first Pentium M–branded CPU, code-named Banias, was followed by Dothan. The Pentium M-branded processors were succeeded by the Core-branded dual-core mobile Yonah CPU with a modified microarchitecture.
A pin grid array (PGA) is a type of integrated circuit packaging. In a PGA, the package is square or rectangular, and the pins are arranged in a regular array on the underside of the package. The pins are commonly spaced 2.54 mm (0.1") apart, and may or may not cover the entire underside of the package.
Xeon is a brand of x86 microprocessors designed, manufactured, and marketed by Intel, targeted at the non-consumer workstation, server, and embedded system markets. It was introduced in June 1998. Xeon processors are based on the same architecture as regular desktop-grade CPUs, but have advanced features such as support for ECC memory, higher core counts, more PCI Express lanes, support for larger amounts of RAM, larger cache memory and extra provision for enterprise-grade reliability, availability and serviceability (RAS) features responsible for handling hardware exceptions through the Machine Check Architecture. They are often capable of safely continuing execution where a normal processor cannot due to these extra RAS features, depending on the type and severity of the machine-check exception (MCE). Some also support multi-socket systems with two, four, or eight sockets through use of the Quick Path Interconnect (QPI) bus.
The K6-III was an x86 microprocessor line manufactured by AMD that launched on February 22, 1999. The launch consisted of both 400 and 450 MHz models and was based on the preceding K6-2 architecture. Its improved 256 KB on-chip L2 cache gave it significant improvements in system performance over its predecessor the K6-2. The K6-III was the last processor officially released for desktop Socket 7 systems, however later mobile K6-III+ and K6-2+ processors could be run unofficially in certain socket 7 motherboards if an updated BIOS was made available for a given board.
Socket 370 is a CPU socket first used by Intel for Pentium III and Celeron processors to first complement and later replace the older Slot 1 CPU interface on personal computers. The "370" refers to the number of pin holes in the socket for CPU pins.
Slot 1 refers to the physical and electrical specification for the connector used by some of Intel's microprocessors, including the Pentium Pro, Celeron, Pentium II and the Pentium III. Both single and dual processor configurations were implemented.
Socket 479 (mPGA479M) is the CPU socket for the Intel Pentium M and Celeron M mobile processors normally used in laptops, but has also been used with Tualatin-M Pentium III processors. The official naming by Intel is µFCPGA and µPGA479M.
The P6 microarchitecture is the sixth-generation Intel x86 microarchitecture, implemented by the Pentium Pro microprocessor that was introduced in November 1995. It is frequently referred to as i686. It was succeeded by the NetBurst microarchitecture in 2000, but eventually revived in the Pentium M line of microprocessors. The successor to the Pentium M variant of the P6 microarchitecture is the Core microarchitecture which in turn is also derived from the P6 microarchitecture.
The Intel 440BX is a chipset from Intel, supporting Pentium II, Pentium III, and Celeron processors. It is also known as the i440BX and was released in April 1998. The official part number is 82443BX.
Pentium is a brand used for a series of x86 architecture-compatible microprocessors produced by Intel since 1993. In their form as of November 2011, Pentium processors are considered entry-level products that Intel rates as "two stars", meaning that they are above the low-end Atom and Celeron series, but below the faster Intel Core lineup, and workstation Xeon series.
The Intel i810 chipset was released by Intel in early 1999 with the code-name "Whitney" as a platform for the P6-based Socket 370 CPU series, including the Pentium III and Celeron processors. Some motherboard designs include Slot 1 for older Intel CPUs or a combination of both Socket 370 and Slot 1. It targeted the low-cost segment of the market, offering a robust platform for uniprocessor budget systems with integrated graphics. The 810 was Intel's first chipset design to incorporate a hub architecture which was claimed to have better I/O throughput and an integrated GPU, derived from the Intel740.