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If someone swapped out your CPU for a slower one, would you notice?

Today morning, I was checking the specs of my CPU when I noticed something weird. Intel Core 2 CPUs are supposed to slow down when they are not under load. Intel calls this feature “Enhanced SpeedStep technology” and it’s designed to conserve energy. But my CPU – a 3 GHz Core 2 Duo – was running at its full clock speed at all times.

When I launched the Task Manager, the cause of the problem became obvious. The CPU was under load: both cores were fully utilized by ORTHOS, a simple program used to stress-test CPUs and RAM. In fact, ORTHOS had been running for 58 hours. I had started it two days ago to heat up my room in the night, and forgotten to shut it down the next morning. (My Radeon HD4850 is a much better heater, but I wanted to effect a gentle increase in temperature, not turn my room into a sauna.)

Chew on this: Over the past two days, I had been using my machine almost continuously and hadn’t realized I had two computationally intensive processes sucking the life out of both CPU cores! (In the interest of full disclosure, there was a brief moment yesterday evening when I thought that skipping forward and backward in a HD video clip took a bit too long, but I put it down to normal differences between video formats.) If I hadn’t checked my CPU parameters this morning, which I did for a completely random reason, who knows how much longer it would have taken me to realize something was amiss.

Now, that wasn’t the first time that I’d had ORTHOS running in the background while using my computer. Those other times, it was a different experience altogether. Applications took a long time to launch, websites took much too long to load – the lack of responsiveness was simply unacceptable. I would have sworn to you that ORTHOS was crippling my PC.

Of course, the only difference between those other times and the last two days was in my head. Back then, I knew I had ORTHOS stressing my CPU, so I expected poor performance, which is why every single operation seemed slow to me. Without that knowledge and that expectation, my PC was, it seems, perfectly responsive.

Today’s experience will make me think long and hard before I decide to spend money on a new CPU. And every time I hear someone say how much snappier their new Intel i7 rig feels next to a Core 2, I will wonder: would they even notice if I secretly swapped out their i7 for their old Core 2?

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10 Comments so far ↓

  • Malcolm

    Here is the problem. CPU priority and threads.

    IMO the reason you didn’t notice the drastic speed decrease was because of the the CPU priority that was set on the benchmarking software. You might re-run it and check the priority in task manager.

    The other question I have is: What OS are you running, because believe it or not I can really tell the difference in compile times between my old 3.0Ghz C2Duo and my 6core AMD (went from about a half hour kernel compile to 10 min).

    • Tomasz

      You may be right — the ORTHOS processes run at “low” priority.

      I don’t doubt that compile times are shorter with a faster CPU. Processor speed is also important for any kind of intensive computation, video/audio encoding, 3D rendering, and gaming. However, if you don’t do much of these things (the vast majority of users don’t), you might find it hard to tell the difference between a new CPU and a 3-year-old one.

      • Malcolm

        In that case, yes. I would notice. It might take me a few hours, but I would definitely notice.

        The real question you want to ask is:
        Can grandma get along with a P4.

  • David

    I play Dwarf Fortress, I would notice.

  • Anon

    You have discovered the dirty little secret that Intel does not want you to know.

    Some time ago CPU performance crossed the threshold of “more than good enough” for most of the tasks that 90-95% of typical computer users perform on their PC’s. I.e., reading/replying to email, most surfing of the web (not youtube/etc., just basic surfing), etc. Which means that there really has not been a pressing need for most to upgrade because what they have now is more than good enough for what they do with the machine.

    But, this realization results in just the conclusion you reached. Do I really need to upgrade??? But that conclusion hurts Intel’s bottom line. So they don’t want you to realize you have “more than enough already” and try long and hard to make you believe that you “need” a quad core i7 just to read your emails.

    Anymore, what makes a difference in performance that most people witness is the speed of their video card hardware in moving pixels, and the speed with which their hard disk can move data into memory. If you could magically couple an old P4 cpu to a modern motherboard with SATA 3G, a modern GPU, and a modern RAM subsystem, you would likely be surprised at how fast it seemed to perform as compared to when you used to have a P4 yourself.

    FWIW this comment was typed on an old IBM Thinkpad T22 (Pentium 3, 700 or 900mhz). Is it as fast as a Duo or i7, no. It is more than enough for 90% of what I use it for, yep.

    • Tomasz

      I’m afraid Intel will win in the end. First I’ll get an SSD, which is an obvious upgrade that everyone recommends. Then I’ll decide I need SATA 3G to make it really fast, so naturally I will need a new motherboard. (Another likely reason is the appearance of USB 3.0).

      Of course, the new motherboard will not work with my current CPU (is this the reason Intel keeps changing the CPU sockets?), so I will have to get a new CPU. And some new RAM because the old sticks won’t work either. I might also need a new PSU, since the new CPU will likely be a power hog. (Wonder when we’re going to break the 1000 watt barrier, by the way.)

  • incuś

    Do you really use your CPU to heat up your room? 😉

    • Tomasz

      Yes, when it’s cold and my central heating doesn’t work. The PC is a pretty good heater: it has a big radiator and there are fans that push the warm air out of the case, which increases efficiency. It’s probably more efficient than an electric heater without a fan.

  • Michael

    No, I probably wouldn’t notice either lol. I used to always get the latest and greatest when I upgraded my PC, then later realize I don’t even need a high end processor except for maybe gaming, and even that’s mostly GPU dependent.

  • new reader

    I’ve got a couple well-powered systems I use for development. One of them is an 8-10 lb (3.6-4.5 kg) laptop. I realized I don’t really any development while on the run, but I do still check email, browse the web, and edit the occasional document. And, I was getting tired of lugging that thing around.

    So, I finally got over my “not powerful enough” thinking about netbooks and took a look at them again. I looked for what was running Windows 7 Home Premium (or Pro) and had full-size keys. Not much to pick from, but I eventually found a nice little machine for a decent price. Connecting to wireless networks takes a little longer than I’m used to, but otherwise I really don’t notice much of a speed difference. Booting actually seems to be faster, since it’s not loading all the baggage required for the development tools.

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