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i7 CPU single core always busy

SZimm4
Beginner
3,713 Views

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!

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AlHill
Super User
1,808 Views

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

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SZimm4
Beginner
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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.

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AlHill
Super User
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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

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SZimm4
Beginner
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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!

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AlHill
Super User
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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

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idata
Employee
1,807 Views

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.

 

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SZimm4
Beginner
1,807 Views

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!

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idata
Employee
1,807 Views

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

 

 

Best regards,

 

 

 

Ivan.

 

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SZimm4
Beginner
1,807 Views

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.

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idata
Employee
1,807 Views

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.
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