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.
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.
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:
The multiplier unlock feature is working great. If you don't have an Extreme CPU then you won't be able to try this new feature because an adjustable multiplier is only supported on Extreme CPUs.
I've heard that many Acer laptops do not have great bios support for Intel's Extreme CPUs with their adjustable multipliers. I decided to post this here first so I can get some feedback.
somebody over on TechPowerUp provided me with some information how to go about doing this while you are in Windows. Adjusting the multiplier higher on an Extreme CPU is possible even if the motherboard bios you are using does not support this feature.
This feature has been added to ThrottleStop 2.51 so let me know if it works for you. Right click on ThrottleStop to bring up a couple of new menu options. Not only can the FID (multiplier) be adjusted as high as you like, you can also adjust the VID higher. Hopefully this is going to open up a few doors for users with Extreme CPUs. Post some screen shots including CPU-Z, so I can see how this is working on Acer laptops and remember to include your Acer model number.
Once you adjust the FID or VID higher than the default setting, this setting will remain in the CPU until you reboot whether ThrottleStop is running or not. To reset both of these settings, there is a right mouse menu option in ThrottleStop called Reset CPU FID/VID which will take your CPU back to its default settings.
If you have an Extreme CPU but it is not being correctly recognized as an Extreme CPU (no new right mouse menu options), post a screen shot of CPU-Z so I can have a look. Some ES processors don't have the correct information written into them but I have a work around ready to handle this.
Edit: A couple of minor updates for version 2.52 and 2.53.
If you have an Extreme CPU like an ES that is not properly recognized as an Extreme CPU by ThrottleStop (ie. no new right menu options to unlock your CPU), you can try adding Extreme=1 to the ThrottleStop.ini configuration file. This trick will do absolutely nothing and might cause problems if you do not have an Extreme CPU.
A Core 2 Extreme CPU should have these two new options available.
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:
The Alienware M11x R2 uses Intel's Ultra Low Voltage Core i5 and Core i7 UM processors. These CPUs are designed to limit the amount of turbo boost when fully loaded which reduces power consumption but that can also significantly decrease performance.
There are two values in the CPU called TDP and TDC that controls when the CPU is allowed to use the turbo boost feature. If your CPU is operating below the turbo TDP power limit and is also below the turbo TDC current limit, you get full turbo boost. If you are over those limits, turbo boost will not be used. The CPU is constantly checking power consumption and adjusting turbo boost accordingly.
If you would like to increase the amount of turbo boost at full load, you need to increase the turbo TDP limit that the CPU is using.
WARNING: Increasing the TDP limit can increase power consumption and can reduce battery life when running on battery power. Any damage caused by using software like ThrottleStop to change this limit is at your own risk.
Download ThrottleStop from the link in my signature.
Click on the TPL button to open up the Turbo Power Limits window.
Most UM processors have TDP set to 10 watts and TDC set to 30 amps.
To get more full load turbo boost you need to increase TDP to 30 or higher.
When finished, click on OK to save your settings.
You can also set ThrottleStop up so it uses different TDP/TDC turbo boost limits for each profile. This will allow you to use your 30/30 limits when gaming and you can use the default 10/30 limits when you are on battery power so there will be no change in your battery life. Use the Options window to set a default AC profile as well as a default Battery profile so this will change automatically.
Increasing the turbo TDP limit within the CPU will help to maintain full turbo boost even when fully loaded. In these UM CPUs, this can increase full load performance by up to 50%. Here's an example of the increase in CPU performance that is possible.
There is also a setting in the Options window called Force TDP/TDC. This controls how often the TDP/TDC settings will be checked and adjusted in the CPU. Setting this value to a smaller number increases the frequency of this. Going too low can reduce performance. The default setting of 16 gives good performance without slowing down the CPU. User testing has shown that a value of 8 or less might help you to maximize your overall CPU performance. If you want to adjust this to maximize performance then do some testing. Use a program like wPrime and you can adjust this value based on your benchmark scores from this program. The quicker wPrime can do a 32M or 1024M calculation, the faster your CPU is running.
The Core i7-920XM and Core i7-940XM in the Alienware M15x and M17x do not need the Force TDP/TDC option set to a low number. Setting this to 1000 or higher should be OK for them to maximize performance. So far, this has only been tested on the M11x but there might be other laptops with Ultra Low Voltage UM processors that can also benefit from this setting.
If your CPU fan is clean and your heatsink is properly attached, the M11x will not use Clock Modulation throttling or Chipset Clock Mod throttling so there is no need to check either of these boxes.
The Set Multiplier box seems to be optional for the M11x. If you use this feature, you need to set it as high as it can go. Keep increasing this until it says Turbo.
The numbers in the FID column represent the average multiplier on each thread in real time. When running a wPrime benchmark and all threads are fully loaded, the average multiplier value in this column should increase after TDP has been adjusted higher. This indicates your CPU is running faster.
Increasing TDP/TDC will show the biggest gains if you are overclocking your CPU in the bios by raising the BCLK value. Using ThrottleStop to increase the TDP/TDC limits may show little to no performance gain if you are not overclocking in the bios.
It might also be possible to decrease the TDP/TDC settings if you are interested in reducing power consumption and extending battery life. This possible use of this new ThrottleStop feature has not yet been investigated.
WiFi Disconnect Problem
When using this new ThrottleStop feature, mcham was having a problem with his Dell 1520 WiFi mini card losing its connection after about half an hour of gaming. His laptop stayed connected when on a wired connection and it also seems to be OK since he switched to an Intel 6300 Ultimate N WiFi mini card. I'll update this info if he is still having problems. Update: this may just be one bad card and not a common problem with the Dell 1520. Other users have had no problem gaming for hours with the Dell WiFi card while using ThrottleStop.
This section lets you customize what your profile names are called. Your name changes will show up in the system tray menu.
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.
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.I'd like to thank somebody over at TechPowerUp who introduced me to this little trick.
Intel Dynamic Acceleration (IDA) on Core 2 Duo CPUs is designed so that the CPU will use a higher multiplier (faster speed) but Intel designed this feature so that only a single core at a time can benefit from this turbo boost. The second core has to be in the C3/C6 sleep state for this to work. As soon as the second core wakes up to process some background task; the maximum multiplier will drop back to the default multiplier. When the second core is finished and goes back to sleep, the first core can go back up to the higher speed by switching to the IDA multiplier.
IDA mode is available in most of the T7000, T8000, P8000 and T9000 series of mobile Core 2 Duo CPUs.
There is finally an easy way to enable IDA mode on both cores at the same time so it doesn't cycle on and off like Intel intended. When testing on a T8100, this resulted in a 9% performance boost when running the multi-threaded benchmark wPrime.
Unfortunately, not all laptops are capable of enabling Dual IDA mode. You need to be able to toggle the SpeedStep (EIST) bit from within Windows. On the Dell D830 I tested, there is an option in the bios so you can disable SpeedStep / EIST but many manufacturers lock the EIST bit and don't provide any option to unlock it. If you don't have this bios option and ThrottleStop shows that the EIST bit is grayed out, that means it is locked and you won't be able to use this trick.
Here's what worked for me.
1) Enter the bios and disable Enhanced Intel Speedstep® (EIST).
2) After you boot up, start up ThrottleStop. It should look something like this.
The multiplier will be stuck at the default minimum which is 6.0. Adjust the multiplier to the highest possible value, set the Voltage ID which is the voltage your CPU will use and check the Set Multiplier box. Click on the Turn On button and then click on the EIST option. You should see the multiplier start to jump around in the monitoring area like this. If the multiplier is not above your default multiplier then make sure that you set the Minimum processor state to 100% in the Control Panel -> Power Options.
The trick now is to disable EIST. This should force the CPU to lock both cores so that they will both be using the highest IDA multiplier. The T8100 I tested has a default multiplier of 10.5 and the IDA multiplier is 11.5. After I disabled EIST, the CPU multiplier gets stuck at 11.5 on both cores.
You can run any sort of program you like and you can stress both cores as much as you like but it won't budge. By lowering the VID voltage to a safe and stable amount, you can run both cores at full speed without creating a lot of heat.
The Intel 45nm T8100 I tested is so efficient that there doesn't seem to be any significant increase in idle power consumption when locked like this. With a Kill-a-Watt meter I couldn't measure any difference. It seems that at idle, the CPU turns itself mostly off no matter what settings you use so this little trick shouldn't significantly change idle power consumption or increase your CPU temperature.
Here's the final result. Both cores are fully loaded while the IDA multiplier is fully engaged on both cores. Core temperatures look great too.
If this trick works or doesn't work for you then post your results and let me know what type of laptop you have and what bios version it is using. Unfortunately some of the Acer laptops don't give you an option in the bios to disable EIST so you are out of luck.
When EIST is disabled, ThrottleStop will not be able to control your multiplier anymore. It will still be able to monitor your CPU and you can use it to lock the clock modulation values but adjusting the multiplier and VID will have no effect. On my laptop, SLFM was also automatically disabled when I booted up with EIST disabled.
If you want the operating system to get control of your multiplier then you will need to enable EIST before you exit ThrottleStop. I left it this way so once you set your CPU to use the IDA multiplier full time, you don't even need to leave ThrottleStop running. Your CPU will continue to use your locked IDA multiplier until you manually enable EIST.
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.
ThrottleStop download link: ThrottleStop