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Intel's 15 Most Unforgettable x86 CPUs

Pentium II and III: Brothers

Released in 1997, the Pentium II was an adaptation of the Pentium Pro aimed at the general public. It was quite similar to the Pentium Pro, but the cache memory was different. Instead of using a cache at the same frequency as the processor (which is expensive), the 512 KB Level 2 cache operated at half-frequency. In addition, the Pentium II abandoned the classic socket for a cartridge containing the processor and the Level 2 cache, which was in the cartridge and not on the motherboard or in the processor itself.

New features compared to the Pentium Pro were essentially MMX (SIMD) support and a doubling of the Level 1 cache. The first Pentium III (Katmai) was very similar to the Pentium II. Released in 1999, its new feature was essentially support for SSE (SIMD instructions), but the rest was identical.

Code nameKlamath (Pentium II 0.35µ), Deschutes (Pentium II 0.25µ), Katmai (Pentium III)
Date released1997, 1998, 1999
Architecture32 bits
Data bus64 bits
Address bus36 bits (32 bits on the P III)
Maximum memory64 GB (4 GB on the P III)
L1 cache16 KB + 16 KB
L2 cacheexternal, 512 KB (1/2 CPU frequency)
Clock frequency233-300 MHz (Klamath), 300-450 MHz (Deschutes), 450-600 MHz (Klamath)
FSB66-100-133 MHz
FPUbuilt-in
SIMDMMX (SSE)
Fabrication process350 nm (Klamath), 250 nm (Deschutes, Katmai)
Number of transistors7,500,000 + cache (Pentium II), 9,500,000 + cache (Pentium III)
Power consumption25-35 W
Voltage2.8 V (0.35µ), 2 V (0.25µ)
Die surface area204 mm² (0.35µ), 131 mm² (0.25µ), 128 mm² (PIII) + cache
ConnectorSlot 1

The Pentium II and III had 512 KB of Level 2 cache (31 million transistors). One Pentium II actually had an on-chip 256 KB Level 2 cache—the Pentium II Mobile Dixon. Using a 180 nm fabrication process, this processor was significantly faster than the desktop versions.

  • Arkz
    great article with only a few slight errors (like saying the core2duo has 1-4 cores... i don't think there's a 1 cored version lol)

    Looking forward to the AMD article.
    Reply
  • aleluja
    To correct you. Core 2 Duo has ONLY 2 cores, not more, not less.
    Core 2 Quad, has 4 cores and Core Solo has 1 core.
    Reply
  • @Arkz

    Yes there is a singal core,

    http://en.wikipedia.org/wiki/List_of_Intel_Core_2_microprocessors#Single-Core_Mobile_processors
    Ok it is not under the same branding but it is part of the same microarchitecture
    Reply
  • Yuka
    I might be wrong, but i resemble that the Pentium 166 (32bits adress bus and all) had support for 4Gb of memory. I remember IBM sold it's top line (at that time) with 64Mb support (even with SDR PC100/66 support). Correct me if i'm wrong please.
    Reply
  • neiroatopelcc
    The core 2 does supply 1-4 cores - 2 cores per die, where one might be disabled, and one or two dies on a socket. It's no less right to call a core2duo a cpu with 1-4 cores, than it is to put the pentium d on the same page as a single core prescot, as it's the very same principle.
    Reply
  • cangelini
    Arkzgreat article with only a few slight errors (like saying the core2duo has 1-4 cores http://en.wikipedia.org/wiki/Coree ... i don't think there's a 1 cored version lol)Looking forward to the AMD article.
    Thanks for the heads-up! I tweaked that passage to better represent the Core 2 architecture's available configurations!
    Reply
  • randomizer
    vosesterOk it is not under the same branding but it is part of the same microarchitecture Exactly. The article says:

    ArticleThere are many versions of the architecture, resulting in configurations with a different number of cores
    There is no mention of the branding, so there is no actual error there, just misinterpretation.
    Reply
  • ImSpartacus
    Arkzgreat article with only a few slight errors (like saying the core2duo has 1-4 cores... i don't think there's a 1 cored version lol)Looking forward to the AMD article.
    http://www.newegg.com/Product/Product.aspx?Item=N82E16819116039
    Yes, it isn't called a "Core 2 Duo," but it uses the Core architecture and only has a single core enabled.

    But I will have to say, there aren't any 3 core models...
    Reply
  • magicandy
    Good to hear you're not only doing an AMD article, but an ATI one as well (in response to the Nvidia article you did earlier, assuming). A sign of class from the new Tom's is a welcome one.
    Reply
  • harrycat88
    I wish they would get rid of those stupid SNAP Linkbubless and Inteltex misguiding links. Who ever invented those stupid annoying double lined text popups should have been burned at the stake
    Reply