If your CPU frequency is being reduced under load, even at low temperatures (below 90°C), then you probably have power limit throttling. Here’s how to disable those power limits.
Warning: disabling your power limits may cause your computer to run at levels of power beyond its design. Even when your CPU itself is protected by thermal throttling, the VRM may overheat and shut your computer down. (If so, you need to give the VRM more cooling like I did here.) Or, when on battery, your system may draw too much power from the battery and shut down. If either of those happens, you should dial the settings back and set an appropriate limit for your laptop, instead of outright disabling them.
Disabling Power Limits
- You need to have ThrottleStop set up. That’s covered in this guide. Make sure you read it before this one.
- Open ThrottleStop.
- Go to the FIVR menu.
- Next to “Disable and Lock Turbo Power Limits“, click Install. Follow the popup’s instructions.
- Checkmark “Disable and Lock Turbo Power Limits“.
- While we’re at it, let’s disable current limits as well. For all components, drag their “IccMax” all the way to the right.
- Click “OK” to close the FIVR menu and open the TPL menu.
- Let’s look at Turbo Boost Power Limits. “Turbo Boost Long Power Max” is known as PL1 and “Turbo Boost Short Power Max” is known as PL2. Both numbers are in watts. Turbo Time Limit is the number of seconds your CPU is allowed to operate at PL2 before dropping down to PL1. Turn off Turbo Boost Short Power Max, which makes PL1 unlimited. Set Turbo Boost Long Power Max to 1023, which is the highest value you can enter.
- Set PP0 Current Limit to 1023 to make sure that’s out of our way.
Now, when you do a stress test, the only Performance Limit Reason (check in HWiNFO) should be thermal throttling. This way, you let no other factor keep you from maximum speed besides the temperature of the CPU itself.
Much like in overclocking and undervolting, run tests to make sure your system is stable with your settings.
- Huawei MateBook X Pro
- Dell XPS 13 2-in-1 7390
A lot of laptops have further Power Limits controlled by the Embedded Controller, which is much harder to change.