Weird 100% CPU usage


New Member
Hi there! As you will see, English is not my first language (by far :tongue:)
Some days ago I noticed after a couple of minutes I start mi PC, my CPU usage goes to a constant 100% , so I checked for viruses and such but MSE gave me nothing and neither Malwarebytes.

Here's the weird thing, I checked the Task Manager to see witch process was causing this and it's always a different process (Sometimes MsMpEng.exe, sometimes dwm.exe and even taskmgr.exe itself) so I started killing processes like a maniac leaving just the few essential ones but nothing changed.
I also stopped all the services with a delayed start, since the problem starts after a couple of minutes but the problem was still there.

Any other idea will be really appreciated.

P.S. My system restore is disabled.


Excellent Member
Microsoft Community Contributor
We need to rule out heat as an issue. It might make the system show high CPU cycles.

Are you watching the Task Manager or Resource manager to see if something is starting up when this happens?

It seems a little strange the utilities you mention would show 100% CPU usage, but I do not know what might be common to all those processes.

Have you tried using msconfig.exe to do troubleshooting? Perhaps start with just letting the Microsoft processes start up? Does it happen in Safe Mode?


New Member
Thanks for your answer Saltgrass.
First of all let me tell you that after restarting in safe mode the CPU issue doesn't seem to be happening anymore, can it be solved just by starting in safe mode? (I didn't use safe mode for years, I completely forgot that it existed)

I will report back if the problem shows up again.

P.S. I will add a couple of things:
It just started to be really cold here in Argentina (winter is coming :tongue:) so external heat is ruled out. I also checked the fans and the thermal paste and it all seems to be O.K.

About witch process was causing it, it's a total random process. Let's say it's SearchIndexer.exe... if I kill that process services.exe automatically takes it's place at the top of the list with a 80% use of CPU and the second in the list uses the remaining 20%

Again Saltgrass, thanks for your time.


Excellent Member
Microsoft Community Contributor
The thinking on running in Safe Mode is that unnecessary drivers or other utilities will not be started. It the problem does not happen in Safe Mode, you might assume one of those things is causing the problem.

You can use Msconfig.exe to selectively start utilities for troubleshooting. Maybe you will find it that way.

If not, there is a utility you can get from SysInternals, a Microsoft Company, called Process Explorer. It is a much advanced version of Task Manager and can divide out threads running within processes, that might be responsible. If you can't find it with that, you can move on the the Process Monitor utility that will watch what your system is doing and create a log.

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