Tradeoff: CPU Clock Speed vs Cache

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If you had two choices in processors, one with 2.7GHz @ 6M cache, and the other with 3.0GHz @ 4M cache, which do you choose?

It would depend which two processors they were and what my requirements were. I believe this question is based on the common misconception that core clock speeds are a measure of CPU performance. They are not. A processor with a higher clock speed may or may not execute more instructions per second than a processor with a lower clock speed. So there's nothing you can do with those clock speeds, you can't compare them against each other.

It's somewhat like trying to judge which of two cars has a more powerful engine by looking at which has a bigger gas tank. Yes, cars with bigger gas tanks tend to have more powerful engines. But the car may just be a gas guzzler, like the Northwood Pentium 4's that had high clock speeds but were awful because Intel sacrificed performance horribly (by extending the pipeline depth) to get the clock speeds up.

Suckers buy CPUs based on clock speeds. Buy based on measured performance on realistic workloads.

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Soviero
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Soviero

Updated on September 18, 2022

Comments

  • Soviero
    Soviero over 1 year

    If you had two choices in processors, one with 2.7GHz @ 6M cache, and the other with 3.0GHz @ 4M cache, which do you choose?

    This is not a shopping question, what I'm looking for is a general rule of thumb for whether greater CPU clock speed or greater cache is better for general purpose, office workloads.

    • G Koe
      G Koe about 10 years
      The answer is, "it depends." Consider editing your question to be more specific, include the processor models and platforms and OS and software that you are using.
    • G Koe
      G Koe about 10 years
      A great general rule of thumb is: "640K is more memory than anyone will ever need on a computer." for general office workloads, a celeron will do just fine. If you are asking about the affect of gHz vs cache on specific workloads, go here:tomshardware.com/answers/id-1626290/ghz-cache.html
    • Soviero
      Soviero about 10 years
      I wanted to keep this a generic "all else being equal" style question. With that said, I'm a Linux admin, so I'll be running Linux (Xubuntu 12.04), multiple SSH sessions, and opening multi-gigabyte text files.
    • Outdated Computer Tech
      Outdated Computer Tech about 10 years
      Product recommendation is considered off topic. How is it not a shopping question, you pointed out 2 specific cpu's and asked which one is better for what.
    • user2824371
      user2824371 over 4 years
      This is not an opinion based question as the OP asks about the difference between clocking (GHz) and the cache
  • Apache
    Apache over 8 years
    Old question, old (but still good) answer. Here is a sidenote: You can find out most processors performance by searching for "CPUTYPE passmark" in a search engine, like Google. For example "i7 4770K passmark". It gives you both single and multi-core performance - measured by Passmark.