How to undervolt Samsung Galaxy S3?

Want to increase Samsung Galaxy S III battery life? Undervolt Samsung Galaxy S3 Quad Core Application Processor is one of the ways to do so. Besides Samsung Galaxy S3 4.8″ HD Super AMOLED screen, Quad Core Application Processor is another big battery eater. Undervolting helps to reduce Samsung Galaxy S3 battery usage, and will make Samsung Galaxy S3 cooler (generate less heat) too. Unlike underclock which may not be so efficient in performance / walt ratio. Undervolt surely will improve battery life because it maintains the overall performance speed while lower the battery usage. As usual, you need to install custom kernel for Samsung Galaxy S3 in order to undervolt. Stock kernel does not support it.

Undervolt Samsung Galaxy S3

How to undervolt Samsung Galaxy S3?

  1. Install Samsung Galaxy S3 custom kernel that support undervolt.
  2. Install SetCPU.
  3. At Voltages tab, select the desire value for each speed stages.
  4. Note – try to reduce 25 mV each time.
  5. Click Apply then.
  6. Run Stress test ~ Stress CPU to test stability (located at Info tab).
  7. That’s all.

Note – Only check ‘Set on Boot’ when you are confident that the undervolted values won’t hang and stable all the time.

Each Samsung Galaxy S3 has its own CPU chipset stability. Other people’s SetCPU voltages settings may not work for you. Therefore, you need to try lot of the settings until you get the lowest voltages and stable for daily use.

  • SimpleJack

    Hey Jayce, is it possible to also undervolt the GPU for the galaxy s3. Can you also make a tutorial for it

    • Yes, if kernel supports it. Will write about it if I found one.

  • BigD

    U just instal tegrak oveclock. it loads a module that lets u oc and uv without custom kernel

  • Elliot

    Hey jayce, May i know ur complete undervolted volt? Because after i undervolt i run stress test for around 15min at least, it shows no problem. But after i used it for sometime, it starts to restart by itself

    • Complete undervolted volt… What do you mean?

      • Elliot

        I want the full list of you post-volting voltage for all mhz

        • Oh, I don’t have because I do not undervolt my SGS3 for the moment. 😉

          • Elliot

            “After i undervolt i run stress test for around 15min at least, it shows no problem. But after i used it for sometime, it starts to restart by itself” Do you have any solution to this?

            • Increase the voltage a bit.

  • Nuj

    Hi Jayce, just wondering, how would we know that undervolting is already good enough? what are the things to note in stability test that undervolting is already enough? Pls. enlighten! Thanks

    • Improve battery life without hang issue during daily usage.

      • Nuj

        CPU at 800mhz with battery temp between 34-35 degrees celsius & no GPU errors, tested for 10minutes? do u think it would be enough? phone doesn’t seem to hang though. what do you think? can u recommend?

        • Hard to tell as your CPU hardware quality might be better than mine. As long as it can reduce battery usage and stable. It is fine.

          • Nuj

            so does it mean the lower the frequency the better battery life? I stand corrected with this concept.

            • Not really. Higher CPU speed with lower voltage is better. You get thing done faster.

  • ken

    @jayce can i undervolt battery voltage? ori come with 3.8v but mine battery showed 4.xxv which the temp hit up in less than 5 min during surfing or play less demanding games that hit up 41~44ºc.. idle 36~38ºc…

    • I don’t think you can do that. Better get another original battery.

      • ken

        seems like my battery kong! stuck at 4.07~4.1v on idle.. if charging can hit nearly 4.2 depend temp as well. thanks bro!