Jump to content


Register a free account to unlock additional features at BleepingComputer.com
Welcome to BleepingComputer, a free community where people like yourself come together to discuss and learn how to use their computers. Using the site is easy and fun. As a guest, you can browse and view the various discussions in the forums, but can not create a new topic or reply to an existing one unless you are logged in. Other benefits of registering an account are subscribing to topics and forums, creating a blog, and having no ads shown anywhere on the site.

Click here to Register a free account now! or read our Welcome Guide to learn how to use this site.


Laptop using 20-40% CPU while idle

  • Please log in to reply
3 replies to this topic

#1 RiceFusion


  • Members
  • 2 posts
  • Local time:01:12 PM

Posted 09 May 2013 - 12:26 PM



I have ran into a problem which makes my laptop use up 20-40% of CPU while idle.

It's been going on for awhile now and i'm clueless how to fix it.


I checked it with Process Explorer and it seems System and Interrupts are behind it.


Any help would be deeply appreciated.



BC AdBot (Login to Remove)


#2 HAv0k


  • Members
  • 23 posts
  • Local time:05:12 AM

Posted 09 May 2013 - 12:48 PM

What model of CPU is it? It could be caused by an old CPU with a newer OS, an infection, or just bloatware/things you've installed running.

#3 RiceFusion

  • Topic Starter

  • Members
  • 2 posts
  • Local time:01:12 PM

Posted 09 May 2013 - 01:06 PM

It's Intel Pentium B970 @ 2.30Ghz.

#4 quietman7


    Bleepin' Janitor

  • Global Moderator
  • 52,047 posts
  • Gender:Male
  • Location:Virginia, USA
  • Local time:07:12 AM

Posted 09 May 2013 - 01:29 PM

System Idle process is used for measuring how much idle time the CPU is having at any particular time (100% minus the sum of all tasks CPU usage). It accounts for processor time when the system is not processing other threads and will display how much CPU resources, as a percentage are 'idle' and available for use. One instance of this process operates per CPU, and runs to occupy the processor when other threads are not running. System Idle process also issues HLT commands which put unused parts of the CPU into a suspend mode, thereby cooling the processor. Normally this process should take up at least 90%+ of processor time on average (this is the value in the CPU column). In non-technical terms, this figure represents how much CPU time has not been requested by anything else on your system. See Why Is The System Idle Process Hogging All The Resources?,

System is a process in NT "kernel mode" that contains most of the system threads and handles various basic system functions. When Windows loads, the Windows kernel starts and runs in kernel mode to set up paging and virtual memory. It then creates some system processes and allows them to run in "user mode" but restricts their access to critical areas of the operation system.

Every process started by Windows, except for the System process, runs in user mode. The User mode processes must request use of the kernel by means of a system call in order to perform privileged operations on their behalf. Kernel mode has full access to system resources and controls scheduling, thread prioritization, interrupt handlers, memory management and the interaction with hardware. The system process cannot be terminated.

For more detailed information, please refer to:
Windows Insider MVP 2017-2018
Microsoft MVP Reconnect 2016
Microsoft MVP Consumer Security 2007-2015 kO7xOZh.gif
Member of UNITE, Unified Network of Instructors and Trusted Eliminators

If I have been helpful & you'd like to consider a donation, click 38WxTfO.gif

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users