Intel's 15 Most Unforgettable x86 CPUs

Pentium Pro: The First To Handle Over 4 GB Of Memory

The Pentium Pro, released in 1995, was the first x86 CPU able to manage more than 4 GB of RAM using Physical Address Extension (PAE), 36-bit address size, and thus 64 GB. An interesting point is that this processor was also the first P6 (the architecture the Core 2 processors are loosely derived from) and also the first x86 to include a Level 2 cache on the processor instead of on the motherboard. In fact, between 256 KB and 1 MB of cache were placed next to the CPU, on the same socket, making the L2 cache on-package as opposed to on-chip, clocked at the same frequency as the CPU.

This processor also had a bit of a performance issue. It ran great in 32-bit applications, but was much slower with software still written in 16 bits (like Windows 95). The cause was simple: access to 16-bit registers caused problems with management of the (32-bit) registers, which canceled out the advantages of the Pentium Pro’s out-of-order architecture.

Intel Pentium Pro
Code name P6
Date released 1995
Architecture 32 bits
Data bus 64 bits
Address bus 36 bits
Maximum memory 64 GB
L1 cache 8 KB + 8 KB
L2 cache external, 256-1024 KB (CPU frequency)
Clock frequency 150-200 MHz
FSB 60-66 MHz
FPU built-in
SIMD N/A
Fabrication process 600-350 nm
Number of transistors 5,500,000 + cache
Power consumption 29-47 W
Voltage 3.3 V
Die surface area 306-196 mm² + cache
Connector Socket 8

The cache measured 202 mm² (256 KB at 500 nm), 242 mm² (512 KB at 350 nm), or 484 mm² (1 MB at 350 nm). The number of transistors in the cache was 15.5 million (256 KB), 31 million (512 KB), or 62 million (1 MB).

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  • 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.
    -4
  • 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.
    7
  • Anonymous
    @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
    3
  • 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.
    1
  • 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.
    -1
  • 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!
    -1
  • 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.
    1
  • 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...
    0
  • 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.
    4
  • 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
    6
  • JonathanDeane
    What Intelitext do you speak of ? lol (I use a good Hosts file from MVP) blocks most of that crud.

    Anyway great article was like a trip down memory lane for me, first Intel CPU I got to use was a 8086 and wow it was slow (I was a kid with ADD give me a break lol) well maybe it was not slow and it was the floppy drive that killed me... Either way best game on it was Qbasic uugghh I think I remember it having CGA with a mighty 4 colors !! I had some paint program for it too.
    0
  • johnlove
    Compared to Athlon, Pentium 4 is a big loser.
    So why is the Pentium 4 "unforgettable"?
    0
  • Anonymous
    My AMD machine (K6 233MHz) smoked all my college buddies Pentium 233s. MatLab, Visio, Quattro Pro, PSPICE, Duke Nukem - everything ran faster on my machine. And it cost me $400 less than the comparable Intel setup.
    0
  • warezme
    Just 15? I figure its anything with SX after it, anything Celeron and most of anything HT (hyperthreading heat trap)
    0
  • warezme
    oops, my dyslexia read the thing as Most Forgettable.., ignore post above. Maybe thats the next article
    0
  • jimmysmitty
    johnloveCompared to Athlon, Pentium 4 is a big loser. So why is the Pentium 4 "unforgettable"?


    Because it was a huge part of CPU history? IDK. Considering that it was not that bad until Prescott, which I am sad they didn't mention.

    But the Pentium 4 will always be remembered in my eyes thanks to the Blue Man Group. Them and their crazy stuff.

    theDagdaMy AMD machine (K6 233MHz) smoked all my college buddies Pentium 233s. MatLab, Visio, Quattro Pro, PSPICE, Duke Nukem - everything ran faster on my machine. And it cost me $400 less than the comparable Intel setup.


    Thats nice. Because this is obviously a competition.

    No wait its not. Its just a nice walk down memory lane and they are going to do AMD next so no need for that.

    I for one am suprised that they didn't include the Pentium 805. I remember reading how well that one OCed and when OCed it smoked the highest end available and it only cost $150 bucks.

    Seriously why bring AMD into this? Its just nice memories not a comparison.
    -1
  • ovaltineplease
    Enjoyed the article, it was a nice walk down memory lane to my teenage nerdhood.
    0
  • snarfies1
    jimmysmittyConsidering that it was not that bad until Prescott, which I am sad they didn't mention.


    If the best you can say about it is "that it was not that bad," that would seem to indicate it wasn't particularly worth remembering.
    0
  • Anonymous
    You forgot the 486DX5 133. Allowed me to up a 486/50 to Pentium 75 performance with just a chip. Worked well till programs started to check for a true Pentium chip before running/installing.
    0
  • theLaminator
    I've got a working luch box with a 386 in it complete with network cards, Working pentium box, a PIII box, the laptop I still use is a P4 3.0Ghz (an hour and half battery life lol), and my new rig has A core 2 duo E8400 OC'd to 4.0Ghz. Good times for me with Intel
    0