LSASS.EXE High CPU Issue

[ITGURU]

I have a laptop which has an issue - several minutes after boot up the laptop goes into overdrive on CPU usage for lsass.exe and the laptop fan is constantly running due to the usage.

If I reboot, the system stays idle for a few minutes at 99% idle but then rockets up on the LSASS process.

 

I've looked into process explorer and find the attached below but not really sure what to do as cannot really find any suggestions as to how to resolve the issue. It seems to be !RtlUserThreadStart running multiple times.

 

I even did a clean install of windows and all the latest system drivers but the issue returned so I know that it isn't malware related etc.

 

Anyone who can help me out on this?

Thanks in advance.