“No need to write an undervolting guide..” they said. (me)
“There’s plenty of great ones on google!” they said (this is still me saying this stuff)
Well it turns out “plenty of great ones” means a bunch of undetailed, poorly organized and contradictory information that may help you, but may also confuse and frustrate.
See I’m not an undervolting expert, but I have done it several times before on different systems. Both the process and the results varied each time, even on two different laptops of the exact same make. Same chassis, same fans, same thermal compound, DIFFERENT results.
So the purpose of this here blog post is to clarify what is the main goal of undervolting, how the different variables we will be tweaking affect the final results as well as make the research and actual undervolting process as easy and foolproof as possible. I’m basically making this guide for myself.
And if I wanted to make the perfect guide for something, it would be a guide that holds my hand through the whole process, so that I don’t have to have a single other browser tab open.
All the information you need will be right here. Just you, me and a whole lot of software.
This will hopefully help you create a nice game plan that’s simple to understand and can be personalized for your own laptop’s CPU, its form factor/chassis and by extension its thermal constraints.
What you’re going to need:
- ThrottleStop – The main software we will be using
- Prime95 – A great free CPU stress-testing software
Very useful stuff though:
- Cinebench R20 – A benchmarking software for measuring your CPU performance
- 3DMark – An optional benchmarking tool you can use for benchmarking alongside Cinebench
- 3DMark Full Version – The full version of 3D mark includes several useful features such as our favorite stress-testing tools, 3D Mark Time Spy and Fire Strike, more precise control over your benchmarks and stress test and more
- MSI Afterburner – Includes an in-game overlay that tracks many useful stats like your average framerates, component temperatures etc.
- Patience – and the power of love and friendship.
IMPORTANT: If you’ve used Intel Xtreme Tuning Utility (XTU) or if you’ve previously tweaked the voltages in your BIOS: Please make sure to BOTH reset all your settings to their default AND uninstall all versions of XTU before you perform any actions within Throttlestop.
Also, while undervolting itself is a relatively simple process with very low risk, ThrottleStop is a powerful tool that gives you access to many sensitive parts of your system. We would recommend that you DO NOT change any settings unless we specifically mentioned it, or if you are unsure what it does. Gaming On Lap is not responsible for any damage caused by irresponsible usage. Do this at your own risk.
Forget all that super important stuff, Back to business.
When you start up Throttlestop, unless it’s like the year 2077, it’ll look something like this:
Right off the bat, here’s what you should be looking at:
- CPU core monitoring
- Each row represents a CPU Thread. The Core i7-9750H in question here has 6 cores and 12 threads
- C0% – this can be thought of as how much of the thread is being allocated to different tasks (in %). Higher number = more demand from your tasks.
- FID or Frequency ID – A shortened version of the frequency value a thread is running at. The “11.53” in the first row means the thread is running at 1153 MHz
- Power usage + Themal stats
- C0% – Indicates average core usage across all cores/threads
- PKG Power + Max – Indicates the current power draw of your system (in Watts), as well as the highest power draw it has reached since you’ve started measuring. This max value can be reset using the “CLR” button under it
- To the right of the C0% value you will see the current temperature of your CPU package as a whole (in Celsius), as well as the highest temperature value it has reached since you’ve started measuring. The max value can be reset using the “CLR” button under it
- Speed Shift
- Your Speed Shift – EPP may be disabled by default. This allows you to control how often your CPU runs at its highest frequency. Valid values are between 0-255, where 0 means your CPU will ALWAYS run at its maximum allowed frequency, and 255 means it will only do so when it absolutely has no other option. You’ll want to have it somewhere in the middle. Experimenting with undervolting will give you a better feel of where you want this to be. If you still don’t know, set it to 128.
- Extra functions that don’t really have a common theme but we good.
- FIVR – Opens the Fully Integrated Voltage Regulator menu. This is where the undervolting is done.
- Limits – This will be one of the more useful menus later on. Whenever your CPU’s power is being throttled, a box will appear inside this menu displaying the reason for the throttling. A red box indicates your CPU is being throttled right now. A yellow box indicates that some throttling has happened, but is no longer in effect.
- TPL – The Turbo Power Limit menu in charge of setting power limits for short and long turbo boost periods. Will help us reduce PL1/PL2 throttling seen in the “limits” menu mentioned above.
- CLR – Press this to clear the “Max” values for both the PKG power and temperature. Very useful for the iteration process.
- There is also an options menu at the bottom left – we’ll need it in just a bit. I ran out of cool colors.
- At the top left, directly under the Techpowerup logo, you have 4 radial buttons. Those are your profiles, by default they are “Performance”, “Game”, “Internet” and “Battery”. They may also be referred to as 1, 2, 3 and 4 respectively.
Now that we’ve acquainted ourselves with the main interface, we can more effectively monitor how the changes we will be making will affect our system, and we can therefore decide whether these changes are good or bad.
The first thing you’ll want to do is set up 2 profiles. One for when your system is plugged into a power outlet, and one for when it is running on a battery.
Open up the options menu in the bottom left and make sure the boxes labeled “AC Profile” and “Battery Profile” found at the top right of the window are checked, with the values “1” in the textbox near AC Profile and “4” for Battery.
Press ok to save.
The Undervolting Process
Now we actually start the iteration process. Open up the FIVR menu in Section 4.
This is the interface that allows us to adjust the voltage settings of our CPU. First, make sure you have the right profile selected at the top left.
Most of our work will be done on the “Performance” profile (1 by default).
At the top mid “FIVR Control” section we will be switching between altering the controls of our CPU Core, CPU Cache, and Intel GPU (or iGPU).
Undervolting means lowering the voltage of your CPU, therefore make sure you are moving the slider to the left, so that the offset has a “-” negative value. Whenever we say increasing the offset, this is what we mean.
In order to change the voltage of one of the components, you must first tick the “Unlock Adjustable Voltage” checkbox for each of the three components we will be affecting.
Under Offset Voltage you will see the main slider and 3 radial buttons labeled “Range”, each with its own voltage offset window.
By default you will have your range window at 125 mV, and I recommend not changing it until you’ve tried the highest possible offset, and it passed a stress test (-125mV).
Even if any of this is confusing so far, once you see the process, everything will become more clear!
In order to see how much of an improvement we get from undervolting, we need to first measure how well our system fares in its default state.
The main interface of Throttlestop also features thermal stats and saves the peak temperature your laptop has reached. Once you run each of the benchmarks, save the max temperature value that is showing in Throttlestop, and then press the CLR button in order to clear that value, so we can see what the peak temperature is for each.
When benchmarking, you may see your CPU’s clock speed drop significantly very suddenly. This is due to thermal throttling, which undervolting helps combat.
Throttlestop is so awesome, that it will tell you what caused thermal throttling to happen. You can access this feature in the “limits” button above the FIVR menu in the main interface of Throttlestop.
Once you run the first benchmark, write down what each box says and under which of the three columns it is located. After you have them all recorded, press “clear” and run the other benchmark.
Different benchmarks may produce different thermal constraints. It’s important to save both because thermal throttling really sucks.
Since these stats will later be used as the “before” photo, feel free to share your pre and post stats in the comments. We may even help you squeeze just a bit more or do some advanced ninja tweaking!
If you want, you can even go to your favorite game and write down some framerate numbers to see what kind of a gain you see. I personally use MSI Afterburner as it is customizable, free and can track many different stats.
When we do the iteration process, we don’t want to start from an offset of zero to save ourselves time.
Instead, Set your CPU Core and CPU Cache offset to -50mV. Also, you can go ahead and set your Intel GPU to -30mV and we will not be changing it any further.
After doing this, run prime95’s torture test for 10 minutes, if you don’t get a blue screen or your system freezes, you’re good to go.
If it does freeze, that means your laptop may have been undervolted from the factory, or the manufacturer set the voltage relatively low. In this case, you can either lower the offset by a bit and try again, if that fails too after a few tries, simply reset your settings to their default values (press the zero offset button at the bottom for each component you’ve changed – and don’t forget to save!).
One last little thing, at the bottom right of the FIVR interface, make sure you have the “OK – Save voltages immediately.” radio button checked and we’re ready to start!
The iteration process
Step 1: Increase the voltage offset on your CPU Core and/or CPU Cache by -5-10 mV (Towards the left)
The smaller your steps are, the more accurate you can be at finding that perfect sweet spot.
2.Press OK to save your new values. Again, make sure you have the “OK – Save voltages immediately.” radio button checked.
3.If you have the full version of 3D Mark, you can run any of the Fire Strike stress tests and you should be fine, as it is very demanding and runs for a decent amount of time.
3D Mark’s full version features thorough stress tests such as Fire Strike and Time Spy that are much less time consuming and will truly push your system to its maximum, which means its results will be more reliable than Prime95, at least in my experience.
If you don’t, you can use Prime95’s Torture Test for about 20 minutes. Running for longer will give you more accurate long-usage results.
Got a crash or get a blue screen? lower the offset by just a bit, and run it again.
If you still haven’t crashed, that means your voltage offset has held up once again, and you can go back to step one.
Each time you run the stress tests successfully (your system survived), compare the voltage offsets with the highest offset you had before.
You know you are done when you reach the offset values that are right on the edge between a crash and a stable system. Hopefully leaning towards the latter.
I’ve noticed that some people recommend running benchmarks right after you’ve found a stable voltage, but what I like to do is take it straight to my favorite demanding game.
This will allow you to track any immediate improvements and give you a real-world test for the new voltage settings.
Don’t be afraid to run several games just to make sure it’s stable. Once you’re done you can start running benchmarks. This is where the curtains really unveil and you can see the improvements first-hand.
Remember to compare your results with the ones you recorded before we started undervolting. This is my favorite part 😀
The final touches
Lowering Turbo max clock speed – Eliminating thermal throttling
You’ve been through so much already, and your laptop is shining through, but Throttlestop has additional features that you can use to further reduce or even fully eliminate thermal throttling.
First, I’d like to note that thermal throttling happens when your CPU or GPU reach a certain maximum temperature set by the manufacturer of your laptop.
Since having your CPU run at high clock speeds increases the heat potential, we can assume that if we lower the maximum clock speed, our laptop will never reach high enough clocks – and therefore high enough temperatures – for throttling to set in.
And lucky for us, it’s a lesser-known fact that your game is probably less demanding of your CPU than you think, which means lowering your maximum clock speed may show no difference at all in-game, while still lowering the potential for heat.
How do we detect thermal throttling though?
Simple! When we recorded our pre-undervolt stats, we used a panel in Throttlestop titled “Limits” which is accessible from the main interface.
Under CPU and GPU you can see the different constraints that have caused your CPU to perform at sub-optimal levels.
For this method, we will be focusing on reducing or even completely eliminating thermal throttling.
In order to change your maximum CPU clock speeds, open the FIVR window from Throttlestop’s main page.
At the bottom left of the FIVR menu under Turbo Ratio Limits you will see different values for clock speeds with each number of processor cores active.
Since we will be gaming, the most relevant option will be the bottom most one from whatever is available. In the case of the photo featured above, we see that there are 6 cores available, and so I will be changing the “6 Cores Active” value.
We will refer to the value you set to when you have every core active as the all-core clock.
Just a quick reminder NOT to use the settings you see in the photo, these aren’t even the settings I use personally, and they are probably not going to give you whatever results you are looking for.
The values you see in your system may be completely different, and that’s fine!
Whatever all-core speed you are running at by default, it’s probably higher than it needs to be. Experiment with lowering to different clock speeds (1 unit at a time. Slow and steady just like the undervolting iteration process) and see if you get any thermal improvements, then take it to the benchmarks and your games library.
If you feel any decrease in performance as a result of lowering all-core speed, then you’ve hit the minimum that your games require. Increase the clock by one unit and voila.
It’s important to once again compare your results. Does running 3DMark or Cinebench produce thermal throttling still? What about playing games? Has the maximal temperature you hit changed at all?
A potential method for reducing PL1 and PL2 throttling
PL1 and PL2 throttling happens when your CPU is either requiring too much wattage, or is not receiving enough of it for some reason while Turbo Boosting. This can also result in sharp reductions in performance for short amounts of time.
Some people have found success completely eliminating this by using Throttlestop’s Turbo Power Limit features.
In the main interface, right near the button for the FIVR interface where we did the undervolting, you will see a button labeled TPL.
Pressing it opens the Turbo Power Limit interface. At the top you will see boxes for “Turbo boost short power max” and “Turbo boost long power max”. Untick the box for “short power max” and set the value to the right of the “Turbo boost long power max” to a higher number than it was before. I have it at 100. Please be careful and use your own judgement or ask in the comments if you are thinking of changing something you are unsure about.
I love undervolting because it feels like a deep look into your laptop’s inner-workings and gives you a better Idea of what it can do and how to treat it.
Take care of your laptops. Clean them out any chance you get. They will reward you with the incredible experiences we seek to help you achieve here at Gaming On Lap.
We hope you’ve been successful and seen grand results.
If you’re still unsatisfied with your laptop’s performance or are still experiencing thermal throttling, we’ve written an article detailing other methods of increasing thermal performance that may also produce significant improvements!
There is a whole lot in this article!
And like we said, we want this article to be as thorough and understandable as possible.
If you think there’s something missing or if there are inaccuracies, or if you just have questions then slap it onto a comment and we’ll get back to you as soon as we see it!