The Pentium 4 has come a long way since its introduction in the Fall of 2000. It went from being a laughable performer, to a CPU embraced by the community. Today Intel is extending the Pentium 4 family with the third major revision of the chip – codenamed Prescott.

Back when Prescott was nothing more than a curious block on Intel’s roadmap, we assumed that history would repeat itself: Intel would move to a smaller, 90nm process, double the cache and increase clock speeds. Intel has always historically behaved this way, they did so with the Pentium III and its iterations, and they did so with the first revisions of the Pentium 4. What we got with Prescott was much more than we bargained for.

Intel did move to a 90nm process, but at the same time didn’t produce a vastly cooler chip. Intel did double the cache, but also increased access latencies – a side effect we did not have with Northwood. Intel also moved to Prescott in order to increase clock speeds, however none of those speeds are available at launch (we’re still no faster than Northwood at 3.2GHz) and Intel did so at the expense of lengthening the pipeline; the Prescott’s basic Integer pipeline is now 31 stages long, up from the already lengthy 20 stages of Northwood. With Prescott, many more changes were made under the hood, including new instructions, some technology borrowed from the Pentium M and a number of algorithmic changes that affect how the CPU works internally.

If you thought that Prescott was just going to be smaller, faster, better – well, you were wrong. But at the same time, if you view it as longer, slower, worse – you’re not exactly on target either. Intel has deposited a nice mixed bag of technology on our doorsteps today, and it’s going to take a lot to figure out which side is up.

Let’s get to it.

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  • mattsaccount - Sunday, February 1, 2004 - link

    From the HardOCP review: "Certainly moving to watercooling helped us out a great deal. In fact it is hard for us to recommend buying a Prescott and cooling it any other way."
  • eBauer - Sunday, February 1, 2004 - link

    I am curious as to why the UT2k3 botmatch scores dropped on all CPU's... Different map?
  • Pumpkinierre - Sunday, February 1, 2004 - link

    Sorry errata on #20 that was 3.0 Northood result is out of kilter with other cpus in dtata analysis sysmark 2004.
  • Pumpkinierre - Sunday, February 1, 2004 - link

    JFK,Vietnam,Nixon,Monica,Bush/Gore,Iraq and now this! - what is going on with the leader of the free world.I hope it overclocks well- that's all that's going for it. Maybe Intel should rethink their multiplier locked policy. AMD must get in there and profit. I still dont understand why the caches are running at half the latency as Northood if they are the same speed and structure? Is it as a result of a doubling in size for the same associativity?

    Good article- needs re-rereading after digestion. Last chart in Sysmark2004 (data analysis) has 3.0 Prescott totally outperformed by 2.8 Prescott and all other cpus. Look like a benchmark/typing glitch.
  • yak8998 - Sunday, February 1, 2004 - link

    first the error:
    pg 9 -
    The LDDQU instruction is one Intel is particularly proud of as it helps accelerate video encoding and it is implemented in the DivX 5.1.1 codec. More information on how it is used can be found in Intel’s developer documentation here.

    No link?

    ===
    "What's the power consumption like on these new bad boys?

    Is anything less than a quality 450watt PSU gonna be generally *NOT* recommended?? "

    I'm going to guess a clean running ~350W or so should suffice for a regular system, but I'm not positive with these monster gfx cards out rite now...

    "Any of you know what the cache size on the EE's will be?"

    If your talking about the Northwood (the p4c's are still considered northwoods, no?), its 1mb I believe.
    (still finishing the article. man i love these in-depth technical articles)
  • Tiorapatea - Sunday, February 1, 2004 - link

    I agree, some info on power consumption please.

    Thanks for the article, by the way.

    I guess we'll have to wait and see how Prescott ramps in speed versus 90nm A64.
  • AgaBooga - Sunday, February 1, 2004 - link

    Much better than the P4's origional launch...

    All I want to know now is what AMD is going to do soon... They'll probably counteract Prescott with high clock speeds but when and by how much is what matters.

    Any of you know what the cache size on the EE's will be?

    Also, the final CPU's based on Northwood are kind of like a car with the ratio curves or whatever they're called, but basically after a point of revving, going any higher doesn't give you as much of an increase in speed as it would at a lower rpm increasing the same amount.
  • Cygni - Sunday, February 1, 2004 - link

    AMD's roadmap shows a 4000+ Athlon64 by the end of the year... which is the same as Intel's. They are aware, im sure.
  • Stlr22 - Sunday, February 1, 2004 - link

    What's the power consumption like on these new bad boys?

    Is anything less than a quality 450watt PSU gonna be generally *NOT* recommended??
  • HammerFan - Sunday, February 1, 2004 - link

    Things are gonna get hairy in '04 and '05!!! My take is that AMD nees to get their marketing up-to-spec or the high-clocked prescotts are gonna run the show.

    I have a question for Derek and Anand: What kind of temps does the prescott run at? what type of cooler does it have? (there's nothing there to support or refute claims that the prescott is one hot potato)

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