How to Undervolt CPU

Undervolting your CPU presents a number of benefits – your CPU draws in less power, so you save more on your bill, improve your laptop’s battery life, and reduce the strain on the processor and the amount of heat it generates.

Undervolting the CPU looks complicated, but it really isn’t. Read on as we walk you through the whole process. 

Before You Start

Before you can go ahead with undervolting your CPU, you first need to know how much you can undervolt and whether there’s any improvement. To do so, you’ll first need to test your processor. Here’s how:

1. Download any benchmarking program you prefer. You will have to use it quite a few times as you undervolt the CPU. A lot of people prefer using ThrottleStop, but the choice is up to you. Just make sure that you can use the software to stress test your CPU.
2. Next, you need to download a program that you can use to track your CPU’s voltage and temperature as you adjust them. We recommend using HWMonitor. 
3. Finally, launch HWMonitor (or whatever software you use for monitoring). Note down the figures you see, especially the peak voltage during the benchmark and the core temperature. 

How to Undervolt Your CPU

While there are many programs you can use for undervolting, we’ll be using ThrottleStop. It’s available only on Windows.  

While it’s used for overriding throttling systems, it also comes in handy for undervolting. So, here’s what you need to do.

Step #1: Download ThrottleStop

Download ThrottleStop from the official website. A zip file will be downloaded. Unzip it and run the .exe file. You’ll see a warning about how the software can make changes to your CPU. Simply click “OK” to proceed.

Step #2: Check Speed Shift – EPP

Once the program opens up, you’ll see a lot of options and a basic overview of your processor’s temperatures. You’ll see an option in the main window saying “Speed Shift – EP” on the left. Check that option.  

Step #3: FIVR

Next, find “FIVR” and click on it. A new window will open up with a lot of options. Here, under “FIVR Control,” find the “CPU Core Voltage” and check the option that says “Unlock Adjustable Voltage.” 

Step #4: CPU Core and Adaptive

Then, tick “CPU Core” and “Adaptive.” With these settings out of the way, you can now finally start undervolting.

Step #5: Adjustments

Start by adjusting the offset voltage. We recommend doing so in small increments, especially if you have an older CPU. First, adjust the millivolt value. This depends on your processor, but you’re good to start with around -50mV. If everything works fine, you can go back, follow the steps again, and set the voltage even lower.

Step #6: Voltage

Next, go to “CPU Cache” and make sure the undervolt has the same voltage value as the CPU Core.

Step #7: Intel GPU

Go to “Intel GPU” and undervolt it by setting it somewhere around 25-50mV. You can also skip this step, especially if you have stability issues. Compared to other settings, undervolting the GPU has a very insignificant effect on your voltage and temperature. 

Step #8: Apply

Once you’re done making all the changes, click “Apply” Your computer can crash here, but that’s nothing to worry about; you just need to repeat the steps and not undervolt it as much. If it doesn’t crash, click “OK.”

Step #9: Test the Voltage

With everything tweaked, you now need to test the new voltages to check that your system stays stable when undervolted. For that, run the CPU-Z benchmark and monitor the temperature and voltage using HWMonitor carefully. Compare these to the values you noted before undervolting; you should see some improvements.

Step #10: Tests

If your computer doesn’t crash during the benchmark, do some more tests to make sure everything’s good. Run the software programs you usually use; your goal is to put as much load on your PC as you can.

Step #11: Repeat

If there are no problems, repeat the steps and start to undervolt in smaller increments, say increments of 5-10mV. Eventually, you’ll come to a value where your computer starts to crash. This helps you determine the lowest voltage you can go to. So, go back to the last stable voltage and click “OK.”  

Summary

Now that you’ve figured out the voltage to undervolt to, there’s just one more thing left to do: you need to change some settings and keep ThrottleStop always on. Otherwise, all the changes will be reverted when you restart your PC. 

So, here’s how to keep ThrottleStop always on:

1. Go back to the main window and click on the Task Bar you see on the left. Then, open up “Option” and click on “Start Minimized” Also, choose “Minimize on Close” and click on “O” to save.
2. Now, you need to ensure that ThrottleStop starts up when you switch on your PC. To do so, search for “Task Schedule” in “Start,” right-click on it, and from the options you see, click on“Run As Administrator.”
3. Once the Task Scheduler opens, go to “Create Basic Task” on the right. Put in “ThrottleStop” in the name and then click on “Next.”
4. On the left, click on “Trigger” and select “When I Log On” Then, click on “Next” and then go to “Action” and choose “Start A Program” This will prompt you to choose a file; find and select the ThrottleStop.exe file and click on “Open” Allow the prompt to open up the properties dialogue when you click on “Finish.”
5. Finally, in the “Properties,” choose “Run With Highest Privilege” and click on “O” to save. Now, the program will launch whenever you switch on the PC and execute the changes you made each time.

Summary

The process is a little lengthy – and even daunting if you’re undervolting the CPU for the first time, but it’s not hard. Don’t be afraid if your PC crashes; remember, that is part of the process and will help you figure out the voltage you can undervolt to. 

And once you find the minimum voltage at which the PC remains stable, save those and schedule ThrottleStop to run with those settings every time you fire up your PC.