10 Replies Latest reply on Feb 10, 2017 6:23 AM by Intel Corporation

    i7 CPU single core always busy

    sudz28

      Does anyone know of any way to determine what process/application is running on a specific core?  I find that a single core on my 8-core processor, almost always core 5, gets to almost 100% utilization very quickly after a reboot and stays there no matter what I do.  I have no clue what this processor is doing, or how to determine what it's working on.  I have downloaded and run the Processor Diagnostics tool and everything passes, but again when I look at my Resource Monitor (in Windows 7), Core 5 shows as being basically pegged.  All I'm running in Firefox, Steam, and some background stuff of course (Avast anti-virus, etc.), but no one process shows as using much CPU at all when I look at Windows Task Manager -> Processes.

      (See included pic of my core usage)

      Thanks!

        • 1. Re: i7 CPU single core always busy
          Al Hill

          There are seven generations of the i7 and i5.  What is the complete cpu model number of each?

           

          Have you disabled ALL of avast's real-time tools?

           

          Provide this information so one of the support staff can further assist.

           

          Doc

          • 2. Re: i7 CPU single core always busy
            sudz28

            Thanks for responding!  I have disabled all Avast processes, yet Core 5 remains pegged.  My CPU model is the "i7-940 Bloomfield Quad-Core 2.93GHz LGA 1366" apparently.  It's got 4 physical cores, 8 logical cores.

            • 3. Re: i7 CPU single core always busy
              Al Hill

              What OS are you running?  And, with avast, did you stop all of their processes or just disable them?

               

              If your OS is Windows 10, your processor is not supported.

               

              Also, personally, I would completely uninstall avast and use something else that is less interfering.  And, you want to check that you do not have more than one real-time anti-malware product running.

               

              Doc

              • 4. Re: i7 CPU single core always busy
                sudz28

                OS is Windows 7 Pro, 64-bit.  I disabled them once, and stopped the service entirely once.

                 

                So it sounds like the ultimate answer to the question is, no, there's no way to correlate what any single core is so busy with to a particular process.

                 

                I'll have to look into what might be a good, suitable alternative to Avast.  I was already getting annoyed with their constant add-on stuff and attempts to 'up-sell' various other products they offer.

                Thanks for your help!

                • 5. Re: i7 CPU single core always busy
                  Al Hill

                  When you do replace avast, make certain that you run their uninstall/cleanup tool afterwards.  They leave several remnants that will continue to interfere with things, especially if you upgrade to W10 later.

                   

                  Doc

                  • 6. Re: i7 CPU single core always busy
                    Intel Corporation
                    This message was posted on behalf of Intel Corporation

                    Hello sudz28,

                    Make sure you run Windows® update and have it updated to latest updates.

                    I have read that this can be cause also by driver doing some conflict in your system so I would suggest to access your computer manufacturer website and to update all the drivers in your system to the latest driver released and as well as your bios.

                    I also have seen some customers rolling back to previous graphics driver version and that solve issues like this.

                    Honestly, it is hard to tell what app is causing the issue especially if you can't see in the task manager, so that’s why we will need to start testing one thing or the other to find out how can it be fixed.

                    Regards,

                    Ivan.

                    • 7. Re: i7 CPU single core always busy
                      sudz28

                      Thanks for the continued suggestions.  I actually think I have it narrowed down to "System Interrupts" doing the damage, although I have no idea what device driver may be responsible.  I generally keep my drivers up to date, although I can certainly check a few of them to rule them out I guess.  I built the desktop myself, so I have to go through each component item by item to see if it needs updating (no central manufacturer to go to for all my driver needs unfortunately).

                      I appreciate it!

                      • 8. Re: i7 CPU single core always busy
                        Intel Corporation
                        This message was posted on behalf of Intel Corporation

                        Thank you for the information, please keeps us posted how it goes.
                         
                        Best regards,
                         
                         
                        Ivan.
                         

                        • 9. Re: i7 CPU single core always busy
                          sudz28

                          I've only gotten one small tidbit of additional information.  The issue seems to be happening post-Sleep with my computer.  If I leave it on and running, it doesn't happen.  If I shut it down and start it back up, it's fine.  Only when I put it into Sleep and wake it back up later do I discover that CPU5 is pegged.  I can't imagine what might be causing this, but there you have it.

                          • 10. Re: i7 CPU single core always busy
                            Intel Corporation
                            This message was posted on behalf of Intel Corporation

                            Perhaps you need a BIOS update, this is an old system, the processor was launch in 2008, and at this point any unexpected behavior can occur.
                             
                            Sometimes we want systems to work for ever but sooner or later they will start giving you problems.


                            Ivan.