31

Starting yesterday, I have a very odd problem on my Windows 10 desktop-- my CPU is constantly running at 100% (according to Task Manager), and it isn't throttling down. Because of this, it's constantly running at 3.3 GHz and the temperatures are rising to the point where the fans kick in at full force. If I go into the Windows power settings screen and manually change the processor power maximum to 50%, then it's capped at 50% frequency (~1.5 GHz), but it never goes below the maximum possible frequency.

The weird thing is, when I look at the process list, there isn't really anything obvious that's triggering it. None of the processes are abnormal, and though the process CPU percentages do add up to 100%, it doesn't make sense to me that each individual process is taking up as much CPU as Task Manager says it is. Everything seems to be "using" a significantly higher amount of CPU resources than it normally does.

As an attempt to diagnose the problem, I've also tried using Process Explorer. The really weird thing is that Process Explorer shows only 1-2% usage when idle, with the System Idle Process taking up the remaining ~98% as I would expect. Again, nothing looks out of the ordinary in the process list, but the processes are showing the levels of activity I would expect in Process Explorer.

I've already run both Windows Defender and Malware Bytes (a virus was my first guess), but nothing has turned up yet.

This same issue also occurs in Safe Mode, so I'm guessing that it's more along the lines of something to do with Windows itself...

So, to recap:

  • Windows 10 Desktop
  • Intel 970, 3.3 GHz, 6 cores
  • Task manager and resource monitor graphs shows 100% usage total
  • No individual process is taking up significant resources in the resource monitor list
  • CPU is not throttling down automatically based on the dynamic load, causing high temperatures and the fan to kick in
  • Process Explorer is only showing 1-2% CPU usage

Before I go uninstalling everything, how would I figure out what's causing the issue if nothing weird is showing up in Task Manager or Process Explorer?

Andrew M
  • 1,005

7 Answers7

53

To fix this, you can run the following two commands, which sets the IDLEDISABLE setting back to "0" and then re-applies the power management configuration.

C:\WINDOWS\system32>PowerCfg /SETACVALUEINDEX SCHEME_CURRENT SUB_PROCESSOR IDLEDISABLE 000
C:\WINDOWS\system32>PowerCfg /SETACTIVE SCHEME_CURRENT

After much debugging, I was able to come to the conclusion that my specific case was related to a bug in the Oculus Rift software. Because the Rift, a virtual reality headset, requires low latency, their software seems to set the IDLEDISABLE power configuration to "1". In certain cases, after taking the headset off, the setting is not changed back to the default of "0".

IDLEDISABLE prevents the CPU from throttling itself, causing heat and the fan noise I observed. Additionally, this manifested in the Task Manager as "100% CPU usage". Process Explorer seems to always discount the System Idle Process and not include it in the total CPU usage, which is why it displayed a lower total CPU usage than Task Manager did.

More information can be found in my post-mortem.

k0pernikus
  • 2,652
Andrew M
  • 1,005
6

In Task Manager, make sure that View -> Update speed is not set to Paused

This caused me some confusion on a Windows 2012 Server as it had a snapshot of processes from some time previous and didn't represent the live load

fiat
  • 2,161
1

Hit Start, type in "resmon", and see if it shows any processes going crazy. As far as Task Manager, click on the Details tab, it shows more useful information.

You may also want to download an AV cleaner like MalwareBytes (the free version is fine) and see if your PC is infected. No legitimate app should be killing your CPU like that.

Steve Freeman
  • 185
1

Before, I used to be able to change the power settings like Andrew M had said.

The fix that originally worked for me was to change my performance plan. Ex going from High Performance to Power Saver.

Windows 10 >> Right click desktop >> DISPLAY SETTINGS >> (under system tab) POWER & SLEEP >> (Related Settings) Additional Power Settings.

Or Go to "Ask Me Anything"/Cortana ( the start menu search feature and type in... "Power Options".

OR

EASIEST WAY ---> Right click the windows 10 logo/start button. Click "Power Options".

I could swap between high performance and power saving and it would reset by itself, but for some reason when I opened skype the fans came on blazing and it would not go below 100%, so I did my method and it didnt change anything this time, ended up finding this backdoor/work-around. Works great, thank you.

Andrews Response worked for me.

RickMc3280
  • 13
1

For me, it turned out to be a power plan configuration. In some instances, setting this back to "Not Configured" will instantly resolve the Task Manager issue.

gpedit.msc > Computer Config > Admin Templates > System > Power Management

Set both of these to "Not Configured":

Select an active power plan
Specify a custom active power plan

If on a domain, run gpupdate /force.

This may not be the resolution for all causes, but at least one. :-) Once this was set back to "Not Configured", Task Manager instantly began functioning correctly.

asheroto
  • 67
  • 9
0

I had the same issue on an MSI Laptop with VR capabilities (GE62VR Apache Pro). I turned off the VR Ready setting on the Dragon Center and voila! CPU back to normal

Istvan Romhany González
  • 1
0

I had the same issue and found the easiest way to fix this.

I tried this on Windows 10 pro only.

Go to start and search "power plan" --> choose "Edit power plan"

Choose "Restore default settings for this plan"

If you did this while opening the task manager windows side by side you should notice that the CPU usage drops suddenly to a normal state.

enter image description here

Nuwan Thisara
  • 130