How to prevent laptop CPU Throttling
Some manufacturers, for example Dell, throttle the CPU of a laptop automatically if the AC adapter used is not manufactured by Dell or can't be recognized.
You may notice huge performance drops when that happens. One solution is to purchase an AC adapter that is manufactured by Dell as it will resolve the issue immediately, another that you use software to overcome the throttling.
Please note that you need to make sure that the AC adapter is suitable and does not exceed its power capabilities when connected to a power outlet and the laptop. It is recommended that you create a backup of important data on the device before you use Throttlestop.
Prevent laptop CPU Throttling
Throttlestop is a free program for Microsoft Windows devices -- all 32-bit and 64-bit version that Microsoft supports are compatible -- that you may use to bypass CPU throttling.
The program has not been created specifically for dealing with Dell's throttling of the CPU but it can stop that type of throttling.
Throttlestop is provided as a zip archive that you need to extract on the local system. The program does not need to be installed and can be run right from the folder you extracted it to.
The program requires elevation and Windows will display an UAC prompt when you start it. Throttlestop may look intimidating on first start as there is quite a lot going on.
Tip: Activate Stop Data to stop the program from updating data in the interface automatically. You can activate data collecting when you require it.
Throttlestop's initial goal was to undo throttling schemes used by manufacturers such as Dell but functionality increased over time to include new features such as overclocking options.
The application supports up to four profiles that you can switch between. The Settings area in the interface can be used to disable certain types of throttling.
Clock Modulation and Chipset Modulation indicate whether the manufacturer is using these options to throttle the processor. If you see values below 100% you have evidence that throttling is going on.
The developer suggests that you enable logging by checking the "log file" option. You can run a benchmark with a click on TS Bench then and analyze the log file to see if throttling is going on. Check the CKMOD and CHIPM columns to find out whether they drop below the 100% mark.
The save location for the log file is listed in the options; you may want to check it before you activate the log file option as it was set to save the log to the administrator user account and not the user account the program was started on.
Developers may use other throttling techniques. There is BD PROCHOT (bidirectional processor hot) which some manufacturers use to throttle CPU. Designed to prevent CPU overheating it is used on some laptops that use third-party power adapters or unrecognized power adapters to throttle CPU automatically.
Throttlestop is a very powerful program that can do a lot more than just stop manufacturers from throttling the CPU automatically.
Undervolting is an option and when you click on FIVR in the main menu a new window opens with tons of options to change all sorts of things.
You may find this guide useful as it goes over most of the options and settings.
Throttlestop makes the changes to the current session only. When you restart the PC you need to start Throttlestop again to apply its settings for the current session.
You may add the program to the Task Scheduler so that it runs automatically on start of the operating system. Check out the following video on how that is done:
Closing Words
Throttlestop is a powerful program to stop manufacturers from throttling CPUs if non-OEM power adapters are used. While that is one of the main purposes, its current version supports options to undervolt or overclock CPUs extensively.
Now You: Do you know if your CPU is throttled?
Latest version has DLL problems on Win 10 64bit, version 8.50 works.
Fot the latest version you’ll need to install both x86 and x64 Visual C++ components on your Windows 10 x64 machine.
Visual C++ Redistributable Packages for Visual Studio 2013 – http://www.microsoft.com/en-us/download/details.aspx?id=40784
What’s so special about Dell-branded power supplies? Is it the same magic that makes genuine HP toner cartridges cost four or five times as much as well-made generic cartridges? Just curious.
Modern power supplies provide operating information to the system they’re plugged into, including the make/model of the power supply.
@John Fenderson: And that may well be a legitimate and useful function, even for a laptop AC/DC converter, but throttling the CPU if an electrically compatible power brick from a competing supplier is used raises consumer-protection and antitrust questions, particularly if the tie-in is not conspicuously disclosed before the laptop is purchased.
@Peterc:
Oh, I agree wholeheartedly. I can’t think of a legitimate technical reason for this behavior, and this looks like nothing but a naked attempt at vendor lock-in to me.
Awesome program, thanks for the refresh !
I didn’t know this! Is there any warning popping up on desktop saying “You using non-proper adapter”?
I don’t think so — when I’ve encountered this, the warning happened on bootup before the OS started loading.
But what if you are using Linux?
With Linux, you can set the CPU speed to anything you like in the OS itself without special tools. It’s not user-friendly, though. You do something like this (you need a separate command for each CPU):
echo >/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
This is also handy to intentionally reduce your CPU speed if you want to do something like extend battery life.
There are also several utilities that let you do this in a more user-friendly way. You might want to check out TLP (not an endorsement, as I haven’t used it): https://linrunner.de/en/tlp/docs/tlp-linux-advanced-power-management.html
If you use KDE, I think I remember there being a plugin that lets you handle these settings through the settings panel, too.
Using this on my old ASUS laptop for many years.
Been using it for years on my laptops. Specially since i have an “u” processor (a lot of laptops have these kinds of things), that are made specially for low power usage so they throttle a lot. I can recommend the program for anyone that wants to get the most juice out of their configs.
Its developer is also highly interactive with the users which is a plus.
Wish I’d know about this a year ago.
My alienware laptop was throttled to 780 MHz! if I didn’t use the correct adapter which is either 180W or 240W and has to be made by Alienware. A 100W dell adapter or a 240W generic both throttled and neither would charge the battery.
Needless to say, performance was terrible at 1/4 the proper speed and I’m pretty sure battery life was reduced, now on the third battery in two years. First replaced on site for free (why??$$) third by me.
The only mention dell makes is some generic “Use of the improper adapter may affect performance” warning. It’s not like people don’t use laptops in different locations and may not want to carry an adapter around with them. The 240W adapter is a bit large!
We have three dell laptops and the AW is the only one that throttles, the other two are older and less powerful though. Our HP envy (junk, literally fell apart, wtf!) did the same thing, wouldn’t charge unless the adapter was HP.
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ThrottleStop.exe – Systemfehler
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Das Programm kann nicht gestartet werden, da mfc120u.dll auf dem Computer fehlt. Installieren Sie das Programm erneut, um das Problem zu beheben.
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OK
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ThrottleStop.exe – Systemfehler
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Das Programm kann nicht gestartet werden, da MSVCR120.dll auf dem Computer fehlt. Installieren Sie das Programm erneut, um das Problem zu beheben.
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OK
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http://tinyurl.com/ybwgyu2f
One day the power plug was not fully inserted in my Dell laptop, but inserted enough for the laptop not to go to battery mode, I got this strange message at startup about unrecognized power source and I noticed the serious performance hit.
>Some manufacturers, for example Dell, throttle the CPU of a laptop automatically if the AC adapter used is not manufactured by Dell
I wasn’t aware of this. I have an XPS15 9550 but never used other chargers than the one it came with. Good to know though. The only CPU throttling it was doing was due to temperatures, and that’s because DELL put too little thermal paste on it. It was reaching 98-99 degrees Celsius. About a week ago I changed its paste and now is all fine. It still reaches 85 degrees Celsius with Prime95 running few minutes, but there’s not much I can do about this, and it’s a fairly unrealistic workload anyway. No throttling though.
I wonder if it works well with Process Lasso.