[arch-general] CPU spikes when lid closed

[David Rosenstrauch]

On 12/3/20 4:35 PM, David Rosenstrauch wrote:
> I've been having an odd problem.
> 
> My laptop works like a charm on its own.  However, when it's connected 
> to a USB-C dock and screen, suddenly apps that were working great start 
> eating up lots of CPU.  (Such as Firefox, Thunderbird, and Zoom.)
> 
> After a bit of debugging, I realized that the issue isn't even whether 
> I'm connected to the dock, but rather whether the laptop lid is open or 
> closed:  close the lid and all those apps eat up CPU; open the lid and 
> CPU drops and everything is groovy.

Finally figured out what's going on here:  apparently the laptop is 
somehow capping the CPU speed at 400MHz whenever the lid is closed. 
(When lid is open it goes up to more like 2-3GHz.)

Going to check and see if there's something in the BIOS that controls 
this behavior.  But if anyone has any idea if there's any way to disable 
that within Linux, pls lmk.

Thanks,

DR