The ThrottleStop Guide

Discussion in 'Hardware Components and Aftermarket Upgrades' started by unclewebb, Nov 7, 2010.

  1. unclewebb

    unclewebb ThrottleStop Author

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    ThrottleStop 9.4

    New Features
    - fixed the FIVR - Disable and Lock MMIO feature for 11th Gen CPUs.
    - added separate reporting of the MSR and MMIO power limits.
    - added feature to disable all C states higher than C1.
    - added access to the Ring Down Bin setting.
    - enabled Limit Reasons for Skylake X.
    - updated driver for improved security.
    - fixed power plan list for languages other than English.
    - changed system monitoring timers being used.

    ThrottleStop 9.3

    New Features
    - added 10850K / 10900K support including a new Turbo Group access window.
    - updated the TPL window and added an option to disable turbo power limit control.
    - added the ability to clear the TPL Lock options if accidentally locked.
    - updated the TS Bench and the C State window for the 10 core CPUs.
    - enabled Limit Reasons support for 10th and 11th Gen CPUs.
    - improved access to the Windows power plans.
    - added access to the PROCHOT offset variable.
    - added AVX offset control for unlocked K series CPUs.
    - added reporting, logging and control of Thermal Velocity Boost and V-Max Stress.
    - added clickable monitoring table headings, including minimum temperature and APIC ID.
    - double click the monitoring table for an extended view if you have more than 8 threads.
    - disabled Set Multiplier access when Speed Shift is enabled.
    - more obvious feedback in the FIVR window when CPU voltage control is locked.
    - fixed log file data writing so log file data gets written to the correct day.
    - changed and fixed the logo selector.

    ThrottleStop 9.0

    New Features
    - replaced the WinRing0 and RwDrv.sys drivers for improved Windows 10 2004 compatibility.
    - first version compiled with Visual Studio 2019.
    - added code to stop ThrottleStop from starting if it previously crashed on startup.
    - added options to adjust the main ThrottleStop font.
    - enabled Limit Reasons access for Intel 10th Gen Core i CPUs.
    - added max temperature and max power consumption to the main screen.
    - redesigned the C States window to include 6 and 8 core support.
    - new Notification Area power icon.
    - added an adjustable PROCHOT Offset feature.
    - redesigned Throttle indicator on the main screen which includes types of throttling.
    - Nvidia MHz reporting added to the log file and to the GPU button.
    - improved consistency between user interface and Notification Area temperatures.

    ThrottleStop Primer

    ThrottleStop - Overclocking Dell Precision M6800

    [Guide] Improving Battery Life on Windows [+Enabling Deeper C States]

    WARNING: ThrottleStop is an Intel Core 2 and Core i performance monitoring and modification tool. Some manufacturers throttle CPU performance to protect their motherboards or the power adapter from being damaged so keep that in mind before making any changes. Using ThrottleStop to overclock or over volt your CPU or to disable a laptop manufacturer's throttling scheme may damage your computer and is at your own risk.

    Guide to Automatically Launch ThrottleStop in Windows 10 by illuzn

    How to Restore Undervolting to Dell Laptops

    Windows 11 Compatibility
    ThrottleStop continues to work correctly in Windows 11 but you will need to disable the Windows Virtual Machine Platform feature. Thanks @werdmonkey4321 for this update.

    Windows 10 Compatibility
    As of October 29, 2017, ThrottleStop has been tested and is working correctly with the Windows 10 Fall Creator's Update, Build 16299.15 and 16299.19.

    Here's more information on how power limits work for Intel CPU's

    ThrottleStop originally started out as a simple tool to reverse some of the throttling schemes used in a variety of laptops such as the Dell Latitude E6400. Since then, many features have been added including the ability to overclock the Core 2 Extreme and Core i K and XM series like the Core i7-920XM mobile CPUs. I'll start with explaining all of the basics first and then get into showing some examples of how ThrottleStop needs to be set up for specific purposes like reducing throttling, overclocking or under volting Core 2 CPUs.

    At the top left of ThrotteStop, you can choose between 4 different performance profiles. You can then manually switch between different profiles by either clicking on 1, 2, 3 or 4 or you can use the system tray menu to change between profiles that way.

    Clock Modulation is a feature built into Intel CPUs that can be used to slow a processor down and throttle their performance internally. There are two main types of clock modulation throttling. I call the second type Chipset Clock Modulation since this type of throttling can be triggered by the chipset. A setting of 100.0% for both of these means that your CPU is trying to run at 100.0% of its designed capability. The monitoring area on the right hand side of TS reports these values as CMod% and Chip%. Any value on any thread that is less than 100.0% is evidence of throttling.

    If your computer does not use either type of clock modulation throttling then don't check either box. The Dell laptops that use this throttling method will use one type of throttling or the other but not both at the same time so there is no reason to have both boxes checked. Run a ThrottleStop log file and check to see if your computer has a clock modulation throttling issue and what type of clock modulation it is using before enabling this feature.

    Set Multiplier lets you select the multiplier of your CPU. For example, a T7500 has a default multiplier of 11 and a bus speed of 200 so it is designed to run at 11 x 200 MHz = 2200 MHz. If you reduce the Set Multiplier value to 9 your CPU will run at 9 x 200 MHz = 1800 MHz which might be able to increase your run time while on battery power.

    On Core i CPUs, this works slightly differently. A Core i7-720QM has a default multiplier of 12. To get the maximum turbo boost out of a Core i CPU you need to set this value to 1 more than the default value. A Set Multiplier setting of 13 (12 + 1) will request full turbo boost from the processor. There is no need to set this value any higher than that.

    Core 2 based procesors allow you to adjust the VID or Voltage ID of the processor. This is used with and controlled by the Set Multiplier check box. Adjusting this value provides a very simple way to under volt your Core 2 CPU which can significantly reduce the heat and power consumption of your laptop.

    Power Saver lets your CPU use its lowest possible multiplier and voltage when idle. On the newer 45nm Core 2 and Core i CPUs, this does not seem to be necessary and provides little to no power savings because at idle, the CPU will be in one of the low power sleep states like C3/C4/C6 which uses a lower VID voltage than ThrottleStop or RM Clock lets you select anyhow. This feature is mostly for the early 65nm Core 2 CPUs like the T7500.

    This post explains the power savings you get on a 45nm Core 2 CPU at idle by adjusting the FID and VID to low values. During my testing, the savings were minimal.

    SLFM stands for Super Low Frequency Mode and is an option on many of the Core 2 CPUs. With this enabled, at idle your CPU will reduce the bus speed in half which will reduce your total CPU speed in half. Here's an example of an X9100.

    11.5 x 266 MHz = 3059 MHz - HFM, High Frequency Mode
    6.0 x 266 MHz = 1596 MHz - LFM, Low Frequency Mode
    6.0 x 133 MHz = 798 MHz - SLFM, Super Low Frequency Mode

    SLFM mode also controls access to the lowest possible SLFM voltages. On many Core 2 CPUs, the minimum LFM voltage is 1.00v. To go lower than this value you must enable SLFM mode. RM Clock uses a similar option which it calls DFFS. This stands for dynamic front side bus frequency switching. I recommend using HWiNFO32 so you can see what voltages and multipliers your Core 2 CPU supports.

    Disable Turbo allows you to easily disable the turbo boost feature of your CPU. Core 2 CPUs call turbo boost Intel Dynamic Acceleration (IDA) but this works very similar to the Turbo Boost feature in the Core i CPUs. If this box is checked and clicking on it does not change anything then that means your CPU does not support turbo boost.

    EIST stands for Enhanced Intel SpeedStep. This needs to be enabled so ThrottleStop can control your CPU. If this box is grayed out, that means the bios has locked this feature so it can not be turned on and off which is common for most laptops.

    BD PROCHOT stands for bi-directional prochot. PROCHOT stands for processor hot which is the signal that is activated within the CPU when it reaches approximately 100C to 105C depending on the model number. This signal is what initiates thermal throttling so the CPU can slow down and keep from over heating. Intel included a bi-directional feature so if something else like a GPU is running too hot, it would be able to send a PROCHOT signal directly to the CPU and force it to cool down so the entire laptop cools down. Very few laptops seem to use this type of throttling. This feature was added for the Asus G51. Disabling this will allow your CPU to continue to run at full speed. Disabling this will not prevent your CPU from thermal throttling at its normal Intel set thermal throttle temperature. By default this is locked and you will need to go into the Options window to unlock it so you can toggle it on and off.

    C States should allow you to toggle the C1E state of your CPU. The Intel publicly available documentation does not fully explain this feature. On a Core 2 CPU, using this feature will cause the average multiplier to randomly hunt up and down at idle. Disable this if you want to avoid that.

    Log File will create a log of your CPU's performance and will save it to a file called ThrottleStopLog.txt in your ThrottleStop folder. The log is only updated to your hard drive once per minute so you will need to exit ThrottleStop to make sure all data gets written to the log file.

    More Data will sample the performance of your computer approximately 8 times a second instead of the usual once per second. This can be used with the Log File option so you can go back and see exactly what your CPU was doing.

    Monitoring Panel

    The monitoring area on the right hand side of ThrottleStop consists of 6 columns.

    FID stands for Frequency Identifier. This is also commonly referred to as the multiplier that your CPU is using. ThrottleStop uses high performance timers within the CPU and can very accurately calculate the average multiplier during each 1 second sample period. If during the previous 1 second, the CPU spent half of its time using the 10 multiplier and the other half of the time using the 11 multiplier, ThrottleStop would report that as 10.50. The multiplier can be changing hundreds of times a second within a CPU so reporting the average multipiler will accurately tell you exactly how your CPU is performing. ThrottleStop uses the method recommended by Intel in their November 2008 Turbo White Paper. At idle or when a CPU is lightly loaded, CPU-Z does not follow this method so you will likely see some disagreement between these 2 programs. CPU-Z does this for more consistent validations.

    C0% is a measurement of what percentage of time a CPU is spending in the C0 state. This is the state when the CPU is working so this number is very similar to a CPU load meter. When clock modulation is being used, the C0% is a much more accurate look at how hard your CPU is really working. It can be completely different than what the Task Manager CPU Usage statistic is showing. If the Task Manager shows 100% and ThrottleStop shows only 75%, that's usually a sign of clock modulation throttling that is slowing your CPU down internally.

    CMod% is Clock Modulation percent and this should always show 100.0% on each thread. 75.0% shows that your CPU is only working internally 75% of the time. This number is an approximation only.

    Chip% is Chipset Clock Modulation and like the above, shoud always be reporting as 100.0%.

    DTS shows the direct reading of the on chip Digital Thermal Sensor. This sensor is designed to count down towards zero as the CPU heats up. Intel designed their processors so thermal throttling starts when this sensor reaches zero on any core. By clicking on the Temp button, you can convert this data to an approximate core temperature value.

    Max keeps track of either your hottest core temperature or how close you got to the thermal throttling point. The CLR button at the bottom will clear this saved data.


    Save will save any changes you have made to ThrottleStop so any changes you have made can be restored the next time you start ThrottleStop.

    Batt displays the battery level of your laptop.

    GPU will show you the temperature of your Nvidia or ATI GPU if the driver supports this. You will need to first go into the Options window to select if you would like to add GPU monitoring to ThrottleStop.

    Options... will open the Options window.

    Turn On / Turn Off lets you decide if you want to use ThrottleStop in Monitoring Only mode or if you want to turn ThrottleStop on so it is actively adjusting the performance of your CPU.

    DTS / CLR are explained above.

    Right Mouse Click Menu Options:

    There are some additional ThrottleStop features that can be accessed by right clicking on the main GPU. There will be different options depending on whether you have a Core 2 or a Core i CPU and whether it is and Extreme CPU or not. All CPUs should have the following 4 options.

    About... will tell you what version of ThrottleStop you are using.

    Update BCLK will recalculate the bus speed or base clock speed your CPU is running at. For most CPUs, the only time you need to recalculate the bus speed is after you use a program like SetFSB or any tool that changes this speed. Constantly recalculating the bus speed wastes CPU cycles, increases power consumption and reduces battery life. Once the bus speed is accurately determined, it doesn't change unless you change it so there is no reason to constantly recalculate this.

    Minimize will minimize ThrottleStop to the system tray / notification area at the bottom right.

    Exit will exit ThrottleStop. Make sure you have saved all changes before exiting.

    Core 2 Extreme Menu Options

    Edit: With v.2.95, these options are now located on the main ThrottleStop window.

    Reset CPU FID/VID will reset your CPU to its default maximum FID/VID values.

    Unlock Max FID/VID will unlock both the maximum FID and VID so you can increase your multiplier and core voltage limits. Be careful when overclocking your CPU. Randomly adjusting the FID multiplier higher can cause an instant crash or blue screen (BSOD). The maximum VID for Core 2 mobile CPUs is 1.5000 so be careful when experimenting. This thread at NBR explains this feature.

    Core i Menu Options

    Edit: With v.2.95, these options are now located on the main ThrottleStop window.

    Turbo Power Limits... menu will open up a new window where you can view what the turbo TDP power and TDC current limits are for your CPU. When your CPU is operating below these limits, you will get full turbo boost depending on how many cores are operating in the active C0/C1 state. When your CPU goes beyond either of these limits, turbo boost will immediately stop. Turbo boost can rapidly cycle on and off when you are near these limits which allows the CPU to limit its power consumption.

    Core i7 Dual Core UM Example

    Turbo Ratio Limits... will open up a window that shows you what FID / multiplier your CPU can use depending on how many cores are in the active state. A Core i7-720QM will have this set to 21, 18, 13 and 13. This means when 1 core is active and the other 3 cores are asleep, that core can use a maximum 21 multiplier as long as it is operating within the turbo TDP / TDC power limits. When 2 cores are active, the maximum drops to 18 and when 3 or 4 cores are active, the maximum multiplier is only 13. If you go over the turbo TDP / TDC power limits then the CPU will turn off all turbo boost and you will be running at the default multiplier which is only 12 for a Core i7-720QM.

    The Extreme CPUs lets you adjust the FID higher and you can also adjust the turbo TDP / TDC limits higher so your CPU can operate at maximum speed even when fully loaded. Some of the Core i5 and Core i7 dual cores will let you adjust the turbo TDP / TDC limits but you won't be able to adjust the multipliers unless you have an Extreme CPU. Using ThrottleStop to adjust the TDP/TDC values higher on the Alienware M11x UM processors has resulted in performance increases of up to 50%. You can read more about that feature here:



    Profile Names

    This section lets you customize what your profile names are called. Your name changes will show up in the system tray menu.

    Notification Area

    This is Microsoft's new term for the system tray area. You can choose to view your CPU or GPU temperature or your CPU MHz here. You can also pick what font you would like to use in the system tray.


    This feature allows you to select an alarm and automatically change profiles based on your CPU or GPU temperature. DTS refers to a direct reading from your CPU temperature sensor which counts down to zero as the CPU heats up. A DTS alarm of 10 means that when the CPU temperature is within 10 degrees of the thermal throttling point, ThrottleStop will change to your selected performance profile. The GPU alarm is in degrees C so if you set a GPU alarm of 90, ThrottleStop will change profiles when it reaches that temperature.

    Default Profiles

    AC Profile - Your computer will use this profile when plugged in.

    Battery Profile - Your computer will use this profile when you switch to battery power.

    Low Battery % - If you set this to 30% then your computer will switch profiles when the batter gets down to this level.

    Low Battery Profile - Lets you select the profile for the above feature.


    Start Minimized - This option will force ThrottleStop to start up minimized to the system tray.

    Minimize on Close - When clicking on the ThrottleStop close gadget, ThrottleStop will minimize instead of exiting.

    AC - On, Battery - Off - This will cause ThrottleStop to go into monitoring mode when you switch from AC to Battery and to switch back to being Enabled when you plug back in.

    Do not reset FID / VID on Exit - By default when ThrottleStop exits, it tries to set your CPU to its Intel default settings which should allow the operaing system to resume full control of your CPU. If you don't want this happening then use this option.

    Unlock Bidirectional PROCHOT - This is a safety feature for the BD PROCHOT feature on the main page. It's generally not a good idea to turn off BD PROCHOT so this might get users to think a little harder about what they are doing.

    ATI GPU or Nvidia GPU - If the graphics driver supports temperature monitoring, ThrottleStop will be able to report and log your GPU temperatures.

    Dual IDA on Start - Dual IDA mode is a special feature where some Core 2 mobile CPUs can have both cores locked at the highest IDA multiplier. This feature will try to force your CPU into Dual IDA mode as soon as ThrottleStop starts.

    Profile 1 - Dual IDA - This option dedicates Profile 1 to always try and use Dual IDA mode whenever you switch to it.

    Here is some more information about Dual IDA mode and if your Core 2 CPU and motherboard bios supports this feature.

    Power Saver C0% - This option lets you adjust the sensitivity of the Power Saver feature. Setting this to a higher number will prevent your CPU from running at full speed until the load increases to a higher value.

    Force TDP / TDC - This option was developed for the Alienware M11x and controls how often the turbo TDP / TDC values are updated in the processor. The M11x seems to reach maximum CPU performance when this value is set to approximately 8. If you don't have an M11x then this should be set to a high value like 1000 or higher.

    Run Program on Profile Change - This is a new feature that lets you select a program to run as soon as you enter a new profile or when yu start up or resume from stand-by or hibernate mode. This is a very useful feature when you are using SetFSB. You can enter the SetFSB file location in this box along with the appropriate command line parameters so when ThrottleStop changes profiles, it can automatically increase or decrease your clock speed by calling SetFSB to do the deed. If you use the SetFSB -q option, this can happen quietly in the background without ever having to see SetFSB.

    This feature might also be useful during an alarm. You could program this feature to run any program or bat file to shutdown or warn you if your computer is running too hot.

    Did you like this Post? Did you learn something from it? Then vote for it in the NBR Amazing Content Contest
    Last edited: Sep 29, 2021
    andr89cher, ekkolp, Tenoroon and 93 others like this.
  2. unclewebb

    unclewebb ThrottleStop Author

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    How To Start ThrottleStop With Windows

    If you want ThrottleStop to start up with Windows 10, Windows 8, Windows 7 or Windows Vista; add ThrottleStop to your start up sequence using the Task Scheduler.

    Open up the Task Scheduler, on the left side highlight Task Scheduler Library and then on the right side, click on Create Basic Task...


    Enter a name for the task, ThrottleStop, and then click on Next.


    For Trigger, choose the option, When I log on.


    For Action select, Start a program and then click on Next.


    In this example, I have created a ThrottleStop folder in the Program Files(x86) folder.


    Click on Browse and tell the Task Scheduler where it can find ThrottleStop.exe

    Click Next to go to the Summary window.


    Before clicking Finish select, Open the Properties dialog for this task when I click Finish

    Now you can review your task to make sure that it has been setup correctly.
    On the General tab select, Run with highest privileges.


    The Triggers tab should look like this.


    The Actions tab should show the program that you want to start.


    Make sure nothing is checked on the Conditions tab.


    On the Settings tab, I only have, "Allow task to be run on demand" checked.


    If an item is grayed out on the Conditions tab or the Settings tab, select the box above it and make sure that the grayed out box is not checked. In the Task Scheduler, a grayed out box is still active and you do not want that so clear these boxes before pressing OK.

    Now reboot and see if it works.

    If you have followed the above method exactly, it should work with or without UAC enabled and whether you are in an Admin or Standard account.

    There is also a guide on page 514 that explains some other start up options that you might be interested in.

    If you would like to run ThrottleStop as a service, check out the example posted by @chumley
    Last edited: Mar 11, 2019
    tijgert, apa64, c69k and 18 others like this.
  3. unclewebb

    unclewebb ThrottleStop Author

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    Here's an example of what percentage of time a CPU can spend in the low power C States when it is idle.

    The entire CPU package can spend over 90% of the time at virtually zero volts when idle in C6 or C7 or C8 if it is supported. Maximizing the time a CPU spends in the deep C States is the easiest way to take advantage of Intel's power saving technology which can significantly increase battery run time. Unfortunately, most manufacturers continue to release laptops without doing any proper testing of this. Something simple like a bad USB2 driver can drop C State residency time by over 30%.

    If your computer is not achieving over 90% in a deep package C State, ask your manufacturer why.
    Last edited: Mar 27, 2018
    apa64, Gaurav Sharma, pheint and 10 others like this.
  4. King of Interns

    King of Interns Simply a laptop enthusiast

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    Lovely, detailed guide! Will come very much in handy to many including myself. Rep given!
  5. Trottel

    Trottel Notebook Virtuoso

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    Wowee. A lot of good information here to digest!
  6. User Retired 2

    User Retired 2 Notebook Nobel Laureate NBR Reviewer

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    Hi unclewebb,

    Great post! Can you please also link TS 2.90 shown in the screenshot? 2.89 link in your signature is missing the Run Program on Profile Change feature and a couple of others.
  7. burebista

    burebista Notebook Enthusiast

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    2.90 is a work in progress. ;)
  8. Easirok

    Easirok Notebook Consultant

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    Unclewebb, do you know off the top of your head what the default TDP/TDC is on the 940XM / m17x?

    I currently have TStop set to 75/62 but can't recall if that was default or if I tweaked it.
  9. JohnnyFlash

    JohnnyFlash Notebook Virtuoso

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    62/62. 10char
  10. ajreynol

    ajreynol Notebook Virtuoso

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    can I has OSX version?

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