Excessive CPU Speed on AC power

[Daniel B·]

So, if I watch any video, from any source, whilst on battery power for my X1 Carbon Gen 7, as you would hope, Task Manager in Windows 10 shows the CPU speed in the Performance tab hovering around only the 1 GHz mark, with the GPU being utilized for video decode, but as soon as I plug in the AC adaptor, the CPU Speed "goes through the roof", with the fan kicking on, with it exceeding 3 GHz, where it apparently doesn't matter what app is being used to play a video, not just the Chrome browser, and other tasks that use the CPU to a good degree also cause high CPU usage (only the process playing the video etc shows high CPU usage).

It's also not just me, as someone with a Gen 12 is having the exact same issue, where at least a Lenovo rep responded, but they aren't providing any helpful suggestions, and I really don't know why they aren't willing to recreate the issue, which I bet they can easily do (I suspect the issue is with Lenovo's power plan, along with "performance" mode, where they extremely limit the options with this): https://forums.lenovo.com/t5/ThinkPad-X ... 098?page=1

P.S. I have of course tried installing all available updates, including the latest BIOS update.

[TPFanatic]

rest assured this is normal behavior and it is actually okay for the laptop to run at full 3ghz or more. this assures the laptop gets processes done as fast as computationally possible.

[Daniel B·]

rest assured this is normal behavior and it is actually okay for the laptop to run at full 3ghz or more. this assures the laptop gets processes done as fast as computationally possible.

Um, I'm not sure why you would think that, where the process should use what's required, and no more, where for merely playing a video it should be using minimal CPU cycles, given that the GPU is handling the video decode, as it does on battery power, where I note that video playback for the 480p videos is perfect at the 2x speed I always play them at (on battery power).

As a matter of interest, I've owned IBM PC compatibles going back to the MS-DOS days, before Windows was even a thing, where I started my career as Software Engineer in 1988, and became a certified Windows developer, and ended up even giving Microsoft a few "pointers" via their MSDN.

[TPFanatic]

Nice to meet you. I'm Bill Gates.

This support article may be of interest to lower CPU even on AC.

https://support.microsoft.com/en-us/win ... 696fdf2de8

[Daniel B·]

Unfortunately Lenovo extremely limit the power options available for their X1 Carbon laptops, and offer no such customization (you can create a new power plan, but this doesn't offer any additional options...), where the best "workaround" is to only use the laptop whilst on battery power, which is sad state of affairs for the once beloved ThinkPad range (it's conceivable that the fault doesn't lie with Lenovo, but Windows 10, but I doubt it, as this issue would be much more well known).

[TPFanatic]

If the laptop is under warranty you can try putting in a service ticket. They may be able to come over with a hammer and just beat the CPU until it stops using 3ghz.

https://support.lenovo.com/us/en

https://youtu.be/0KDdU0DCbJA?feature=shared