Task Mgr shows "System" consistently using 50% of CPU, with Nothing Running

I have a Sony Vaio VGN-FW495J Laptop with Intel Core2 Duo CPU P8700 2.53Ghz - no slouch of a machine when I bought it 2+ yrs ago, running Windows 7 64-bit Ultimate SP1.

Recently I had suspicion to think that its performance was being impacted (taking a long time to get to Windows Explorer files and open them up, etc.) even though I am running a properly configured SSD, have a full 8GB of Memory, and My Windows Experience Index is way up.

So I went into Windows Task Manager and saw that my "CPU Usage" was a bit over 50%.  I then went and killed all non-essential Processes, but - even after letting my system "settle" (i.e. go completely & literally - untouched) for several hours, I observed in Windows Task Manager that the "System" (PID = "4"; Description = "NT Kernel and System") was the culprit - it was this process that was consistently using about 50% of my total CPU.  NOTE:  just to be clear - this is Highly Unusual - I've never seen this occur before.

Can't figure this one out - from a user/GUI perspective, the system isn't Doing Anything (i.e., I'm not running any user or background programs, and I don't have a whole lot of extraneous Services running - in fact, apart from AVG 2012, NO non-MS Services are running).

QUESTION:  Is There Any MS Windows utility - or third-party utility - that anyone attending these forums can recommend to 'pick apart' / 'detail' whatever it is specifically that the "System" is doing that is using that 50% of my CPU?

Question Info

Last updated October 17, 2019 Views 28,957 Applies to:

There was a driver from "New Software, Inc." for a product called "Folder-Lock", which is used to be able to assign a password to access windows folders, that was getting invoked by the Win7 System Kernel.  I uninstalled this product, and presto, problem gone - no more 50% of CPU being used by system - - -

How I Did It::

I couldn't find any software or features within "Xperf", "Windows Process Monitor", or "Windows Process Explorer" that allowed me to "map" the offending Thread ID to the responsible driver.  However, Windows Process Explorer does display info for all the Drivers being loaded/invoked for a given process - including the "System" kernel process.

So I just went and slowly browsed thru all 173 of them, and thought about what non-Microsoft drivers might possibly have something to do with locking up resources - a clue given to me by the Starting Address for the offending TID from Process Explorer:


Normal "human heuristics logic" - - -

Thanks JW for the tip on Process Explorer - I had it installed already but really hadn't thought of using it - - -

Could have sworn I didn't see this problem until recently though - and I've had this product installed for several months - - - Oh Well, that'll just be one of those continuing "mysteries of Windows" - - - which provides the opportunity for many thousands of geeks to be gainfully employed - - -

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