Root SetCPU on stock rom and kernel

[esthernrob]

i just rooted my Evo yesterday... (hurray for me)... here's my question... will setcpu work correctly, be effective, still running stock rom and kernel? at this point i'm happy that i've taken the step to just root my phone... i'm quite pleased with the stock set up for now... have been reading alot about battery conservation, phone performance and want to give setcpu a try but i read in a review that it will only "work" if i have a "overclock kernel"... is this true? should i not use this app until i do flash a different kernel? any advice on this is greatly appreciated...

 

[akazabam]

You can use setcpu with the stock ROM (doesn't affect it at all really) and the stock kernel, but you will be somewhat limited. First, you'll need to disable perflock. Setcpu has an option to do this. You only need to do it once, and only on the stock kernel. Once it's done, you can use profiles or set the main setting within 245 MHz and 998 MHz. You cannot overclock unless you flash a custom kernel that has a higher maximum. You will also be limited in governor choice. Governors determine under what conditions the CPU should be scaled to a certain frequency. Each one operates a little bit differently, and some have better battery savings potential than others. With the stock kernel, you only have a couple to choose from.

 

[SMALBA]

Are there certain profiles that we should use? What would you recommend for saving battery?

 

[Muellersirch]

I have the following profiles on my phone (some of the freqs are outside of the supported speeds for the stock kernel, but this will give you a general idea)

Parameters MAX MIN Priority Governor
Screen Off 245 128 70 On Demand
Temp > 40.5 844 128 60 On Demand
Charging 1190 128 50 On Demand
Batt < 20% 729 128 40 On Demand

Most of my battery saving is done by Juice Defender (Paid Version, well worth it), which also has the ability to underclock the processor when the screen is off. I prefer to use SetCPU for the processor because it gives me a little more control over things.

 

[akazabam]

Those are some pretty common profiles. Read this guide for information on how to set them up along with some good examples. Just remember - the more profiles you have, the more it has to poll. If you have a lot of profiles, it doesn't matter if they're designed to save the battery; they will likely be making it worse. Screen off, temperature, and charging profiles are probably the only ones you *need*.