Prescott's Little Secret

In learning about Prescott and trying to understand just why Intel did what they did, we came to realization: not only is Prescott designed to be ramped in speed, but there was something else hiding under the surface.

When overclocking a processor, we can expect a kind of linear trend in performance. As Northwood's speed increases, its performance increases. The same is true for Prescott , but what is important to look at is increase in performance compared to increase in clock speed.

Prescott 's enhancements actually give it a steeper increase in performance per increase in clock. Not only can Prescott be clocked higher than Northwood, but as its clock speed is increased, it will start to outperform similarly clocked Northwood CPUs.

We can even see this trend apparent in our limited 3 clock speed tests. Most of the time, the 2.8GHz Northwood outperforms the 2.8GHz Prescott, but the percentage by which Prescott is outperformed decreases as clock speed increases, meaning that the performance delta is significantly less at 3.2GHz.

Business Winstone 2004

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
1.48%
3.00GHz
0.00%
3.20GHz
0.46%

Content Creation Winstone 2004

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-3.57%
3.00GHz
-5.67%
3.20GHz
-5.43%

SYSMark 2004

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
1.19%
3.00GHz
2.27%
3.20GHz
2.70%

SYSMark was one of the only applications to show a positive performance improvement for Prescott, and we see that with clock speed that advantage continues to grow over Northwood. Keep on reading, it gets even more interesting...

Aquamark - CPU Score

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-2.87%
3.00GHz
-2.47%
3.20GHz
-0.84%

Halo

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-0.18%
3.00GHz
-0.18%
3.20GHz
0.00%

GunMetal

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-0.29%
3.00GHz
-0.58%
3.20GHz
-0.29%

UT2003 - Flyby

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-2.62%
3.00GHz
-1.46%
3.20GHz
-0.86%

Clock speed goes up, Prescott performs more like Northwood.

UT2003 - Botmatch

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-3.55%
3.00GHz
-3.09%
3.20GHz
-2.05%

Warcraft 3

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
1.96%
3.00GHz
1.12%
3.20GHz
0.72%

We continue to see that as clock speed increases, the gap between Prescott and Northwood decreases as well.

Quake III Arena

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-1.33%
3.00GHz
-0.49%
3.20GHz
1.28%

Quake becomes the textbook case of what should happen to Prescott performance as clock speed increases; although initially it is slightly slower than Northwood at 2.80GHz, by the time we reach 3.2GHz Prescott holds an advantage over a 3.2GHz Northwood. This is exactly the trend we expect to see over time, especially once we get close to 4GHz.

Jedi Knight: Jedi Academy

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-7.63%
3.00GHz
-6.85%
3.20GHz
-7.04%

Wolfeinstein: Enemy Territory

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-5.53%
3.00GHz
-4.94%
3.20GHz
-3.79%

DivX Encoding

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-1.30%
3.00GHz
-0.61%
3.20GHz
-0.38%

3dsmax R5

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-9%
3.00GHz

-9%

3.20GHz
-9%

There will be some scenarios that do not work in Prescott's favor, and in those cases Northwood will still remain faster.

Lightwave 7.5

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-7.7%
3.00GHz

-7.3%

3.20GHz
-6.8%

Although to a much lesser degree, we are seeing the same sort of scaling with clock speed in applications like Lightwave. It looks like our theory about Prescott's performance is correct.

Visual Studio Compile Test

  Percentage Increase in Performance from Northwood to Prescott
2.80GHz
-8.2%
3.00GHz

-5.7%

3.20GHz
-3.8%

Much like Quake, our compile test is another perfect example of what clock scaling will do to the Northwood/Prescott gap. As the clock speed goes up, the performance delta decreases.

Development Workstation Performance Final Words
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  • terrywongintra - Monday, February 2, 2004 - link

    anybody benchmark prescott over northwood in entry-server environment? i'm installing 3 servers later by using intel 875p (s875wp1-e) entry server board n p4 2.8, need to decide prescott or northwood to use. Reply
  • sipc660 - Monday, February 2, 2004 - link

    i don't understand why some people are bashing such a good inovation that was long overdue from intel.

    a pc that doubles as a heater and at only 100-200W power consumption.

    Let me remind you that a conventional fan heater eats up a kilowatt/hour of power.

    Think positive

    * space reduction
    * enormous power savings (pc + fan heater)
    * extremly sophisticated looking fan haeter
    * extremly safe casing. reduces burn injuries
    to pets and children.
    * finely tunable temperature settings (only need
    to overclock by small increments)
    * coupled with an lcd it features the best
    looking temperature adjustment one has ever
    witnessed on a heater
    * child proof as it features thermal shutdown
    * anyone having a laugh thus far
    * will soon feature on american idol
    the worst singers will receive one p4 E based
    unit each. That should make people
    think twice about auditioning thus making
    sure only true talent shows up.
    * gives dell new marketing potential and a crack
    at a long desired consumer heating electronic
    * amd is nowhere near this advancement in thermal
    thechnology leaving intel way ahead


    hope you enjoyed some of my thoughts

    Other than that good article and some good comments.

    on another note i don't understand why people run and fill intels pockets so intel can hide their engineering mistakes with unseen propaganda, while there is an obvious choice.

    choice is Advanced Micro Devices all until intel gets their act together.

    go amd...
    Reply
  • Stlr22 - Monday, February 2, 2004 - link

    INTC - "Intel roadmap says Prescott will hit 4.2 GHz by Q1 '05. My guess is that it is already running at 4 GHz but just needs to be fine tuned to reduce the heat."


    Maybe they are trying to keep it under the 200watt mark? ;-)
    Reply
  • INTC - Monday, February 2, 2004 - link

    I think CRAMITPAL must have sat on a hot Prescott and got it stuck where the sun doesn't shine - that would explain all of the yelling and screaming and friggin this and friggin that going on. "Approved mobo, approved PC case cooling system, approved heatsink & fan - and you better not use Artic Silver or else it will void your warranty..." gee - didn't we just hear that when Athlon XPs came out? It brings to mind when TechTV put their dual Athlon MP rig together and it started smoking and catching on fire when they fired it up the first time on live television during their show.

    Intel roadmap says Prescott will hit 4.2 GHz by Q1 '05. My guess is that it is already running at 4 GHz but just needs to be fine tuned to reduce the heat. I bet the experts (or self proclaimed experts such as CRAM) were betting that Northwood could not hit 3 GHz and look where it is at today. Video card GPUs today are hitting 70 degrees C plus at full load but they do fine with cooling in the same PC cases.
    Reply
  • CRAMITPAL - Monday, February 2, 2004 - link

    Dealing with the FLAME THROWER's heat issues is only one aspect of Prescott's problems. The chip is a DOG and it requires an "approved Mobo" and an "approved PC case cooling system", a premo PSU cause the friggin thing draws 100+ Watts and this crap all costs money you don't need to spend on an A64 system that is faster, runs cooler, and does both 32/64 bit processing faster. How difficult is THIS to comprehend???

    Ain't no way Intel is gonna be able to Spin this one despite the obvious "press material" they supplied to all the reviewers to PIMP that Prescott was designed to reach 5 Gigs. Pigs will fly lightyears before Prescott runs at 5 Gigs.

    Time to GET REAL folks. Prescott sucks and every hardware review site politely stated so in "political speak".
    Reply
  • Stlr22 - Monday, February 2, 2004 - link

    ((((((((((((CRAMITPAL)))))))))))))))




    It's ok man. It's ok. Everything will be alright.


    ;-)
    Reply
  • scosta - Monday, February 2, 2004 - link

    #38 - About your "Did anyone catch the error in Pipelining: 101?".

    There is no error. The time it takes to travel the pipelane is just a kind of process delay. What matters is the rate at witch finished/processed results come out of the pipeline. In the case of the 0.5ns/10 stage pipelane you will get one finished result every 0.5ns, twice as many as in the case of the 1ns/5 stage pipeline.

    If the pipelines were building motorcycles, you woud get, respectively, 1 and 2 motorcycles every ns. And that is the point.
    Reply
  • LordSnailz - Monday, February 2, 2004 - link

    I'm sure the prescotts will get hotter as the speed increases but you can't forget there are companies out there that specializes in this area. There are 3 companies that I know of that are doing research on ways to reduce the heat, for instance, they're planning on placing a piece of silicon with etch lines on top of the CPU and run some type of coolant through it. Much like the radiator concept.

    My point is, Intel doesn't have to worry about the heat too much since there are companies out there fighting that battle. Intel will just concentrate on achieving those higher speeds and the temp control solution will come.
    Reply
  • scosta - Monday, February 2, 2004 - link

    You can find thermal power information in the also excelent "Aces Hardware" Prescot review here:
    [L=myurl]http://www.aceshardware.com/read.jsp?id=60000317[/l]

    In resume, we have the following Typical Thermal Power :
    P4 3.2 GHz (Northwood) - 82W
    P4E 3.2 GHz (Prescot) - 103W

    Note that, at the same clock speed and with the same or lesser performance, the Prescot dissipates 25% more power than Northwood. This means that with a similar cooling system, the Prescot has to run substancially hoter.

    As AcesHardware says,
    [Q]After running a 3DSMax rendering and restarting the PC, the BIOS reported that the 3.2 GHz Northwood was at about 45-47°C, while Prescott was flirting with 64-66°C. Mind you, this is measured on a motherboard completely exposed to the cool air (18°C) of our lab.[/Q]

    So, what will the ~5GHx Prescot dissipate? 200W ?
    Will we all be forced to run PCs with bulky, expensive, etc, criogenic cooling systems?. I for one wont. This power consumption escalation has to stop. Intel and AMD have to improve the performace of their CPUs by improving the CPU archytecture and manufacturing processes, not by trowing more and more electrical power at the problem.

    And those are my 2 cents.
    Reply
  • CRAMITPAL - Monday, February 2, 2004 - link

    Prescott will never go above 3.8 Gig. even with the 3rd revision of the 90 nano process. Tejas will make it to just over 4.0 Gig. with a little luck but it won't be anything to write home about either based on current knowledge.

    Intel has fallen and can't get it up!
    Reply

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