100% CPU usage while on AC power - System Interrupts problem

Question

I have been having the same issue that others have been experiencing here, here, and here. When you search for this you see many results. 

My symptoms:

• On battery power, computer behaves "normally".
• Immediately after plugging AC charger in, Task manager reports 100% CPU usage and never drops from that. The fan on my laptop runs constantly because of this.

The culprits in the Task Manager appear to be "System", "System Interrupts" and "Desktop Window Manager".  See this screenshot:

The CPU usage of these three tasks jumps up and down between 30% and 0%, but the total CPU usage is always reported as 100%.

Steps I have taken:

1. Restart in safe mode (same issue)
2. The steps outlined in this post
3. Restart many other times.
4. Remove peripheral hardware.

I ran performance monitoring as outlined in this post. I can link the results from a shared OneDrive folder if that would be helpful. 

Here is a screenshot from that:

Where my mouse is (around 6 seconds in) is when I plugged in my laptop. There is a small spike in System (4) processes, but those go back down. When looking at task manager during this time, CPU usage is at 100%, but this performance trace does not report the same thing as seen here:

Any help would be appreciated!!

I am running Windows 10 Version 1903 (OS Build 18362.592)

Dell XPS 15 9570 (Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz[Cores 6] [Logical/Core 2])

Answer 1

Hi Peter,

seems this is incorrect driver installed.

Use methods described in https://docs.microsoft.com/en-us/windows-hardwa...

or third-party tool LatencyMon to diagnose problem.

Answer 2

Thanks Igor!

I checked out LatencyMon and have been getting reports similar to this:

High interrupt to process latency and high DPC routine execution time. 

What would you suggest next? I have been going through and disabling various drivers without success.

Answer 3

Check for BIOS updates. clean internal cooling system from dust.