Pentium III and Celeron – Coppermine
Pentium III processors based on the Coppermine core showed up in late 1999. These early models operated at 500 to 800 MHz. In March 2000 Intel introduced faster variants of 850, 866 and 1000 MHz. Around this time Intel decided to discontinue support of Slot 1, PIII 1 GHz (100 and 133 MHz FSB version) were the last processors for Slot 1. However It was still possible to use Slot 1 to Socket 370 adapter to fit faster CPUs to older Slot 1 boards. During summer and autumn of year 2000 Intel released Pentium III 900, 933, 1100 and 1133 MHz. The fastest one was very problematic - even if equipped with bigger heatsink, increased voltage and restricted compatibility to only some motherboards, it simply wasn't stable. Intel couldn't solve this problem and because of that PIII 1.13 GHz had to be recalled.
In 2001 Intel managed to solve the instability at higher clock with Coppermine D0 stepping (sometimes also called Coppermine-T) and PIII 1.13 GHz was again available. Besides PIII 1.13, Coppermine-T core could be also found in slower variants of 800, 866, 933 and 1000 MHz (all running at 133 MHz FSB). This stepping could be easily recognized by different marking style and some even had IHS.
Half a year after Pentium III Coppermine, Celeron based on the new 180 nm technology were ready. The L2 cache was limited to 128 kB and compared to the PIII, bandwidth was also reduced. All Celerons up to 766 MHz ran at 66 MHz FSB, which was rather limiting. Just like Pentium III, Celeron Coppermine supported SSE - which allowed significant performance increase in some applications. Till the end of year 2000 many Celeron models were introduced - starting at 533 MHz and with steps of 33 MHz all the way up to 766. In 2001, Intel finally decided to lift the 66 MHz FSB lock and all new models starting at 800 MHz and up to 1100 MHz utilized much faster 100 MHz bus speed.
|Slot 1, Socket 370, 423, 478 chipsets|
|Chipset||SMP||RAM type||Max. FSB||Max. RAM||PCI||AGP|
|Intel 440BX||yes||EDO, SDR||100 MHz||1024 MB||2.1||2×|
|Intel 820||yes||RDRAM||133 MHz||1024 MB||2.2||4×|
|Intel 840||yes||RDRAM||133 MHz||4096 MB||2.2||4×|
|Intel 810E||no||SDR||133 MHz||512 MB||2.2||-|
|Intel 815EP||no||SDR||133 MHz||512 MB||2.2||4×|
|VIA Apollo Pro 133A/T||yes||SDR||133 MHz||2048 MB||2.1||4×|
|Apollo Pro 266(T)||yes||DDR||133 MHz||4196 MB||2.1||4×|
|Intel 850||no||RDRAM||400 MHz||2048 MB||2.2||4×|
|SiS 645||no||SDR, DDR||533 MHz||3072 MB||2.2||4×|
Pentium III and Celeron – Tualatin
Shortly after fastest Coppermine processors, Intel was ready to introduce the last Pentium III generation based on the new Tualatin core. Tualatin had transistor count of 44 million and die size of 80 mm2. The new 130 nm manufacturing process allowed to significantly decrease operating voltage (from 1.75V to 1.45V) and increase frequency at the same time. Tualatin still used Socket 370, but due to some changes it wasn't compatible with older motherboards. Later, unofficial modifications were discovered, that allowed to run Tualatin even on old i440BX boards.
Unlike older Pentium III Katmai and Coppermine, the new Tualatin PIII had some artificial restrictions. The L2 cache was limited to 256 kB and SMP support was not active. Fully active Tualatin with SMP and 512 kB of L2 cache only appeared in the new Pentium III-S product line. These were intended for workstation or server use, but unofficially worked in regular desktop motherboards as well. In July 2001, following models were announced - PIII-S 1000, 1133 and 1266 MHz. Later, in January 2002, the last Pentium III was introduced, the PIII-S 1400. Regular PIII (non-S) were available in 1000, 1133, 1200, 1333 and 1400 MHz variants.
Tualatin Celeron was very popular. Just like older generation, in this case L2 cache was also half-deactivated and had somewhat lower bandwidth. However 256 kB L2 was good enough for P6 architectire to provide respectable performance. FSB remained at 100 MHz, which allowed easy 33% overclocking of Celeron 1000 and 1100. The resulting performance was very good considering the price. All PIII and Celeron Tualatin were produced in FC-PGA2 package with IHS.
In November 2000, Intel introduced brand new architecture, which was supposed to replace older but still very competitive P6. NetBurst architecture was optimized for high frequency and memory bandwidth. The original plan was to scale the architecture up to 10 GHz with more advanced manufacturing process. After few years it was clear these plans were very far from reality.
The first chip based on NetBurst was Pentium 4 1.4 and 1.5 GHz, both launched November 20th, 2000. P4 Willamette was made using 180 nm process, with die size of 217 mm2 and transistor count of 42 million. At the time PIII topped out at 1.1 GHz, so 1.5 GHz of P4 was significantly more. But it came at price of much higher power consumption and double the pipeline lenght (20 stages for Willamette). Also the cache structure was reworked completely. The data L1 cache was reduced to only 8 kB, but with inreased bandwidth and reduced latency. Instruction cache stored already fetched and decoded instructions, with capacity of 12 000 instructions. L2 cache of P4 Willamette remained at 256 kB (just like PIII Coppermine), but with increased bandwidth and also longer latency.
Another innovation of NetBurst was much faster FSB. While PIII utilized SDR bus at 133 MHz (1066 MB/s) and Athlon used DDR bus at 266 MHz (2.1 GB/s), Intel developed completely new bus to be used for Pentium 4. The base frequency was 100 MHz, but the data was transfered four-times per clock - using 64-bit bus width and affective clock of 400 MHz, this meant bandwidth 3.2 GB/s. To saturate such bandwidth, very fast memory was required. SDRAM was too slow and DDR wasn't available in 2000. The only choice left was RDRAM memory. It was used earlier on some Pentium III boards, but due to slow FSB they could never reach the full potential. On the other hand, the new i850 chipset with dual-channel RDRAM (32-bit) running at 800 MHz was a good match for early Pentium 4, both memory and FSB bandwidth equal at 3.2 GB/s.
Processor so much different from its predecessors obviously required new motherboards. Socket 423 and shortly after Socket 478 were introduced. Socket 423 CPU consisted of two parts - 423-pin interposer with PGA interface and the processor itself in BGA package. The BGA processor was soldered to the interposer. Socket 423 was the last PGA Socket with an option to mount heatsink directly to the Socket (just like older Socket 7, 8, 370 or AMD Socket 462). However most of the motherboards were equipped with heatsink mount assembly attached to the board, so plastic clips on the Socket were rarely used. Less than a year after initial P4 launch, Socket 423 was discontinued and Intel produced P4 processors for new Socket 478. S478 was modern micro PGA design, which was better suited for Pentium 4's power and cooling requirements.