Undervolting vs Power Limiting

[Utlaegur]

Hello, I use ThrottleStop to limit my Short Power PL2 instead of undervolting, also use FPS capper via RivaTuner. Is there any reason why undervolting can be a better option for gaming? I mean it just works fine and prevents extreme Watt drops but still would like to use the most of my CPU without wasting any power that I could get.

 

[unclewebb]

Power limiting and undervolting are two different things. Undervolting can reduce power consumption so the CPU can run faster. For many games that are GPU limited, a faster CPU is not necessary. In this situation, limiting the CPU power and forcing the CPU to throttle might not cause any significant decrease in performance.

like to use the most of my CPU without wasting any power

That is why most people undervolt. Using more voltage than what a CPU needs to be 100% stable will increase power consumption. This will increase temperatures and it might increase fan noise as your computer tries to dissipate that excess heat. Lowering the voltage does the opposite. Less voltage equals less power consumption, less heat and less fan noise.

it just works fine

That is all that is important. Set your computer up however you like.

 

[Utlaegur]

Thank you so much for the reply, unfortunately I am using an older laptop for playing mostly CPU intensive games (League of Legends) so my GPU is always around 40% usage whereas my CPU can max out. And after playing some time I noticed that when I don't use TS, CPU Watt value goes down from around 20 W to 7 W and an FPS around 50. I try to limit the CPU W to 14 W so it is sustainable in longer gaming sessions but I am wondering if Undervolting instead would be a better and more playable solution.

 

[unclewebb]

CPU Watt value goes down from around 20 W to 7 W

Post screenshots of the main ThrottleStop window as well as the FIVR and TPL windows. Attach a log file with at least 15 minutes of gaming that shows the throttling problem. Your CPU should not be dropping down to 7W. Perhaps some different settings in ThrottleStop might help fix that problem.

What laptop model do you have? Many Dell laptops with throttling problems like this cannot be fixed.

 

[Utlaegur]

I will be attaching the files as soon as possible, I am currently using an Acer Aspire A515-51G

 

[unclewebb]

Acer Aspire

Some Acer laptops are similar to most Dells. They use an embedded controller EC to set power limits lower than the TDP power rating of the CPU. ThrottleStop does not have access to the EC power limits. Whatever conditions that are used to trigger EC power limit throttling are not publicly documented by manufacturers.

I try to limit the CPU W to 14 W so it is sustainable in longer gaming sessions

Avoiding triggering EC power limit throttling is about all you can do. Some EC throttling might be triggered by a separate temperature sensor that monitors the keyboard temperature. Some manufacturers are afraid there will be complaints if a user's fingers get too hot so they throttle the hell out of the CPU to avoid this.

 

[Utlaegur]

Avoiding triggering EC power limit throttling is about all you can do. Some EC throttling might be triggered by a separate temperature sensor that monitors the keyboard temperature. Some manufacturers are afraid there will be complaints if a user's fingers get too hot so they throttle the hell out of the CPU to avoid this.

Interesting, thank you for the information!

About getting the log file, TS seems to function even though I have disabled the controls, which prevents the game to consume above a certain threshold. I need TS to not function to get accurate readings with the logs file and record the moment my CPU limits itself to use 7 W (I'm thinking it's because of overheating as you've mentioned.). I've attached my current TS settings.

The thing is both FIVR Undervolting and TPL Power Limiting seems to resolve this issue, what I'm not sure is which one would be more efficient as a solution. I feel like it would be better to set a Power Limit and let the CPU figure it out, but then comes the issue if CPU needs to draw more power to provide stable performance when there is no overheating, it won't be able to and that will limit the extra FPS I could've gotten without limiting (Power Limit enabled = Max stable FPS: 80, Power Limit disabled= Max stable FPS: 120 but only for a couple of minutes.). When CPU is undervolted does it effect every power level from minimum to maximum to provide lower temperatures overall like "current volts - undervolt amount" as long as it is used? Sorry for a messy response, I'm only starting to optimize my CPU and there are a few missing links.

 

[unclewebb]

I need TS to not function to get accurate readings with the logs file

Disable Controls is checked in the TPL window. That means ThrottleStop is not doing anything. It is not setup to modify the turbo power limits in any way. Just run a log file so I can see what the problem is and so I can make some recommendations.

The FIVR screenshot shows that Windows Virtualization Based Security (VBS) is enabled. If you want to use the FIVR voltage control features, you have to disable VBS. Start by disabling Windows core isolation memory integrity. Follow the links in my signature if you need help with this. Delete the ThrottleStop.INI configuration file and reboot after you get VBS disabled. Post an updated FIVR screenshot so I can see if VBS has been properly disabled.

You can also run msinfo32 to see if VBS is disabled or not. Some users prefer maximum Windows security over voltage control. You cannot have both so you need to decide what is most important to you.

 

[Utlaegur]

Getting the pure log files without TS activating is not possible, even though I have it disabled PL1 gets activated whenever I'm playing, is there a workaround to this?

 

[unclewebb]

PL1 gets activated whenever I'm playing

Most Acer laptops with low power U series processors will power limit throttle whether ThrottleStop is running or not.

Getting the pure log files without TS activating is not possible

I disagree. I am still waiting to see a log file. Why is it so difficult to share that information?

 

[Utlaegur]

Here is a log file from yesterday, quite a busy log but we cannot see CPU W dropping below 15 (except idle) because it's being clamped by TS even though my TS is disabled as I shared my settings previously.

 

[Utlaegur]

Today it somehow triggered with the same settings around 16:20, probably because I overloaded the CPU with bunch of Chrome tabs (afterwards I disabled BD PROCHOT). But besides this moment it still does not budge UNLESS I close the TS app from taskbar. Here are my settings again for reference, I don't have speedshift or power limit currently.

 

[unclewebb]

it somehow triggered with the same settings around 16:20

The log file shows lots of PL1 power limit throttling right at 15W which is what a low power CPU should be doing when the turbo power limits are set to their default values.

At 16:20:22, things suddenly change. BD PROCHOT throttling begins and locks the CPU to the 4 multiplier. Reducing the CPU speed from 3000 MHz to 400 MHz makes a computer unusable, especially if you are in the middle of a game.

   DATE       TIME    MULTI   C0%   CKMOD  BAT_mW  TEMP    VID   POWER
2025-02-04  16:20:20  26.69   41.1  100.0       0   82   0.9614   14.5   PL1
2025-02-04  16:20:21  29.17   30.0  100.0       0   82   1.0253   14.5   PL1
2025-02-04  16:20:22   5.21   54.3  100.0       0   75   0.5728    4.9   BDPRO
2025-02-04  16:20:23   4.00   78.9  100.0       0   74   0.5773    3.9   BDPRO
2025-02-04  16:20:24   4.00   96.3  100.0       0   73   0.5773    4.0   BDPRO
2025-02-04  16:20:25   4.00   93.3  100.0       0   72   0.5779    4.2   BDPRO
2025-02-04  16:20:26   4.00   95.0  100.0       0   72   0.5779    4.1   BDPRO
2025-02-04  16:20:27   4.00   90.6  100.0       0   71   0.5776    3.9   BDPRO
2025-02-04  16:20:28   4.00   95.4  100.0       0   70   0.5779    3.9   BDPRO
2025-02-04  16:20:29   4.00   95.8  100.0       0   70   0.5773    4.0   BDPRO
2025-02-04  16:20:30   4.00   90.7  100.0       0   69   0.5773    4.0   BDPRO
2025-02-04  16:20:31   4.00   88.6  100.0       0   69   0.5829    4.1   BDPRO
2025-02-04  16:20:32   4.00   82.1  100.0       0   69   0.5828    4.5   BDPRO
2025-02-04  16:20:33   4.00   76.8  100.0       0   67   0.5829    4.2   BDPRO

Try updating to ThrottleStop 9.7.2

This new version includes a feature that should allow you to lock BD PROCHOT in the disabled position. This should prevent your computer from randomly enabling BD PROCHOT. This type of throttling is beyond excessive and is rarely if ever necessary.

I plan to re-write the BD PROCHOT code someday soon so if the latest TS version works or doesn't work, let me know.

 

[Utlaegur]

Thank you so much for all the information, I will update the application and will let know if anything unexpected happens.