Started this morning to have 100% CPU on Windows 8.1, but without any process that causes it (at least in task manager)

Tried several fixes, like disabling the maintenance services, the anti-malware service, and even the windows defender. Nothing helps.

In addition, Normal reboot and even booting to safe mode still produces the same problem.

Malwarebytes Anti-malware does not find anything.

If I look at the task manager, anything running will consume full CPU cores, regardless of what the process is doing, and if nothing is being run, I get 100% CPU with all processes marked at 0.

UPDATE: Using msconfig to disable non-vital services on next boot provides good results, but doing normal boot followed by stopping all services that can be stopped does not. The only two directions now are: Disabling one service at a time and rebooting, or clean install of windows. Neither seems pleasant.

2nd UPDATE: I gave up and decided to upgrade to Win10 to see if that solves it. Guess what, it didn't. Finally did a clean install, and only then I got rid of this $#17. Thanks to anyone who tried to help.

100% without any process doing anything

Service processes taking full cores

Started firefox on blank page

Process Explorer and Task Manager Conflicting

  • Please specify the type of your CPU and Motherpoard.
    – Shapperd
    Aug 13, 2015 at 7:51
  • It's an Alienware 14 laptop, so I'm not sure which motherboard, but the CPU is a Core i7 4900MQ @ 2.8GHz
    – Photon
    Aug 13, 2015 at 7:53
  • 1
    download.sysinternals.com/files/ProcessExplorer.zip Maybe you can try this app, it gives more detailed information aout what is happening in your computer :)
    – Shapperd
    Aug 13, 2015 at 7:55
  • Added image of both task manager and process explorer. They seem to be conflicting. Unfortunately, the fan and the battery usage agree with the task manager and not the process explorer.
    – Photon
    Aug 13, 2015 at 8:10
  • If we stay at the built-in process explorer (i'm suprised about processexps faliure ... ) it shows firefox.. Have you tried disabling plugins, themes anything you can?
    – Shapperd
    Aug 13, 2015 at 8:15


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