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Root is everyone leaving the cpu speeds as is?

Leave it on 1000/300 on demand.

I set some profiles though:

600/300 in standby -- 300/300 was very slow to bring up the menu when I got a call

800/300 when battery is less than 31% -- honestly, I can't really even tell the difference between 1GHz and 800MHz, still really fast.

Have you noticed a difference on the battery drain yet?
 
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I'd be cautious about limiting your CPU speed. On laptops that reduces performance and *reduces* battery life. For intel processors, race to idle is your best bet, and I have no reason to suspect that the DroidX's processor is any different.

To put it in simple terms, modern processors use virtually no power while they're idle. They do use less power to run at 300 MHz compared to 1000 MHz, but the difference isn't proportional to clock speed. Generally it's something like 70% power usage for 300 MHz compared to 100% for 1000 MHz. So, if the processor might take 1 second to do something at 1000 MHz, which requires 100% power for 1 second. At 300 MHz it'd take 3 seconds to do the same thing, and use 70% power for 3 seconds, which is equivalent to 210% power for 1 second. Therefore, it uses twice as much power overall.

Just for fun, this also explains how a widget can use virtually no CPU but kill your battery life. Some widgets (e.g. live wallpaper) update their graphics several times per second. (Note that the graphics don't need to actually change, it might just redraw the same thing 30 times per second.) This will keep bringing the processor out of its power saving "idle" mode.
 
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I'd be cautious about limiting your CPU speed. On laptops that reduces performance and *reduces* battery life. For intel processors, race to idle is your best bet, and I have no reason to suspect that the DroidX's processor is any different.

To put it in simple terms, modern processors use virtually no power while they're idle. They do use less power to run at 300 MHz compared to 1000 MHz, but the difference isn't proportional to clock speed. Generally it's something like 70% power usage for 300 MHz compared to 100% for 1000 MHz. So, if the processor might take 1 second to do something at 1000 MHz, which requires 100% power for 1 second. At 300 MHz it'd take 3 seconds to do the same thing, and use 70% power for 3 seconds, which is equivalent to 210% power for 1 second. Therefore, it uses twice as much power overall.

Just for fun, this also explains how a widget can use virtually no CPU but kill your battery life. Some widgets (e.g. live wallpaper) update their graphics several times per second. (Note that the graphics don't need to actually change, it might just redraw the same thing 30 times per second.) This will keep bringing the processor out of its power saving "idle" mode.


I'm surprised no one has responded to this. Is this really so, and if so, what's the advantage to using SetCPU to lengthen battery life?


~
 
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I wouldn't use SetCPU for that purpose. Since you have to have root, if you really wanted to lower your max CPU speed, you can do it via the overclock script method. The difference is that you underclock the frequencies rather than overclock.

I think most people use SetCPU to make custom profiles. IE, run normal ondemand frequencies most of the time, but have other profiles for when the screen is turned off or the battery is running low on power, etc.

That being said, I have ended up not using SetCPU for any of this. I use it only when I am trying to verify frequencies when I play with overclocking, etc.
 
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I wouldn't use SetCPU for that purpose. Since you have to have root, if you really wanted to lower your max CPU speed, you can do it via the overclock script method. The difference is that you underclock the frequencies rather than overclock.

I think most people use SetCPU to make custom profiles. IE, run normal ondemand frequencies most of the time, but have other profiles for when the screen is turned off or the battery is running low on power, etc.

That being said, I have ended up not using SetCPU for any of this. I use it only when I am trying to verify frequencies when I play with overclocking, etc.


What's the purpose for the profiles if it isn't to either maximize speed at certain times or attempting to lengthen the battery life? Well, I guess you can set a lower speed for high temps, but there are profiles for when the battery gets low as well.
 
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Now with OC aps, the game changes and I can use SetCPU to monitor monitor the conditions that I want to set up where and when to OC. :D

Normal conditions is 400-1450. :D

Just curious, what are your SetCPU settings now? I believe I closely followed something you had set up before (though I probably won't run higher than 1.3 just to be "safe"). And how do you determine what priority to use per profile?


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True you don't want to run underclocked all the time for all reasons.

The side piece missing here is if you underclock and undervolt. Which some are doing, I suspect.

I for one don't need to leg out my battery anymore, as I intend to charge it everynight anyway.

However, underclocking while fully in idle is not the worst idea. But remember, there has to be some process running in the background checking CPU (and ram) usage and then bumping clockspeed as necessary.

Might actually be better off letting the device do its thing. Anybody seeing any credible battery life enhancement.
 
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True you don't want to run underclocked all the time for all reasons.

The side piece missing here is if you underclock and undervolt. Which some are doing, I suspect.

I for one don't need to leg out my battery anymore, as I intend to charge it everynight anyway.

However, underclocking while fully in idle is not the worst idea. But remember, there has to be some process running in the background checking CPU (and ram) usage and then bumping clockspeed as necessary.

Might actually be better off letting the device do its thing. Anybody seeing any credible battery life enhancement.

I am experimenting with mine underclocked at ulv today, just to see if I notice an improvement in battery life. However, the preset max was 800Mhz, but my CPU is still running at 1Ghz, so I hope at least the voltages are lower. I do have SetCPU set to drop speed for high temp and low battery. Of course, it's still going to depend on how much I use the phone today. I'm usually around 30% by mid-afternoon with moderate usage.


~
 
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